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I was surprised by that too. Walts description of the wire hook kinda sounds like the way the rear bench seat bottoms are usually clipped in.

Continuing where I left off on 4/2, the eBay seat track arrived. I tested the motors before I went to install it and none of the three motors responded to the 12V applied to them. NOT GOOD. I contacted the seller and he immediately refunded my payment and told me to keep the seat track. With this recent seat track in my possession, I was now able to try to mix and match parts to get one good working seat track. On a separate occasion, I had previously ordered and received a working set of seat motors, so I went about installing these motors on this latest seat track and plugged it into the wiring harness in the car and tested it. The motors worked, but now I have a new problem. The power seat transmission is verschmeckled I have no working transmission to put in! Regroup time again. With limited options, I decided to throw money at it and buy a rebuilt seat track and put that in. It requires me to send in my old seat track, but fortunately I have the verschmeckled one to give him and I still retain my original for possible use on the passenger side seat. I plan to see if I can fix the bad motor and repair the transmission or to mix and match parts to have one that works. Typical C4 repair gone amuck! Stay tuned.

I'm getting a lot of experience on C4 power seats. My driver's seat track had the center motor of the tri-motor unit that was non-working. It turns out that the center motor drives the seat forward and back. I took the motor unit apart to see if I could fix it. Once I got inside all looked pretty good, but when I rotated each motor I found that the center motor would not rotate. It was stuck in the lower bearing. A little tapping with a small hammer and punch and it released easily. I cleaned both the shaft and bearing and it rotated as well as the other two motors. Once reassembled, I plugged it into Corvette wiring and all three motors operated according to the movements of the controls. I'll set this motor unit aside now as a spare.

What a crazy concoction of engineering there... Even in the 90's I would think there would be a better way to handle that. How much would you say that three motor assembly weighs?

-BP

It weighs 2.1 pounds.
It is a beefy motor, but it drives a transmission that uses plastic gears to move a seat and driver back and forth. I have two bad transmissions in my possession now.
There are rebuilders out there now and people are printing the plastic parts needed for them.

The rebuild seat track arrived today and now the driver's side seat controls work as they should. I tested the seat motors on the passenger side a few days ago and all three are working, but the seat will not move even though it's motor runs. I plan to remove the transmission from the now spare seat track and take it apart to see if I can make it work and use it on the passenger side. But that's low priority for when I run out of things to do.

I started work on one of the extra seat transmissions. Here's a look at the inside when you split the cases. Here are all the parts cleaned up. Looks like I need a replacement for the main gear support and one shaft end cap. All the gears and shafts look good. I found a guy in Texas that prints these parts. He told me the breakage is caused when the seat is run against it's normal front and rear stopping points. There is no protection designed into this system to protect against that.

ODO: 106,262

I attended YouTube University and completed the rebuild of Silvia's passenger seat transmission. Here's the picture of success.[Youtube]https://youtube.com/shorts/Zqpj3vlMZ_U?feature=share[/Youtube]

You are now an expert! Has to be many more of these needing rebuilt - could be a side business.

I couldn't have done it without the know-how and parts from Richard Finley in China Spring, Texas. He provided an excellent video and some used plastic parts for a reasonable price. Very helpful guy. He also prints the plastic parts for this transmission as well as providing a rebuilding service.

ODO: 106,293

While I have the passenger seat out, I thought it would be a good time to treat it with Leatherique Professional Leather Restoration product. There are two parts to the kit, a Rejuvenator Oil and a cleaner. The first step is to generously slather the Rejuvenator oil over the entire seat and rub it into all the seams, and crevices. Then, wrap it in plastic wrap to marinate for a day in the sun.Next use the cleaner to remove all the Rejuvenator along with its accumulated dirt, then wipe it clean with a dry cloth. I've already done the driver's seat and there is a noticeable improvement.

OK, both seats are finished. Both have full movement and a good and thorough cleaning and rejuvenation. I'm amazed at the great condition of these seats. There is virtually no wear and tear for 106K miles and 27 years of use.

Those seats do look amazing.

-BP

Wow, those turned out really nice. C4 seats seem to be notoriously bad, almost every one i see for sale has failed upholstery.

ODO: 106,364

I spent a lot of time this week working on Silvia. A lot of the work was self inflicted. It all started with another foray into Sport Seat refurbishment.
While installing the rebuild kit from my Texas friend, I realized that I have overlooked a problem beyond those that I had already fixed (stuck motors and broken transmissions). It turns out that the basic frame of the seat track has three articulating joints that must articulate if the seat works correctly. The seat track that I was working on had a bad case of corroded/rusted joints. One of them required heat to get moving. Finally after many hours of work I had all three moving sufficiently to complete the rebuild of the seat track. This effort got me to thinking about seat track joints in the other seat track now operating on the passenger side. I decided that I now needed to go back and check that. I found that it was in much better condition but still needed some work to get it loosened up enough. Long story short I mixed and matched the best components of both seat tracks so as to use the best one car and keep the other on for a spare.
There's more...The driver's side seat has two bundles of wires that follow the track as it moves forward and back. Someone had previously been working in this area and did not attach these bundles to seat track. They were left to pull on the connectors as it moved. There was no strain relief and no way of knowing how this attachment was accomplished. It took many hours of trial and error and some modifying of the seat base itself to get a satisfactory strain relief system.So as of now, All functions of both seats are fully operational and I have a spare working seat track in case of trouble in the future.