I started the process of replacing the seat yesterday. I finished installing the upholstery on the seat bottom before it got too dark. Here are the pictures:

The old seats look pretty good in the pictures, but the splits in the driver's side would soon spell it's doom.

This is the old seat bottom and new seat frame. The task is to take the seat rails from the old seat and install them on the new frame.

Old sliders on the new frame. The studs on the old sliders fit the holes in the new frame perfectly. All I had to do is drill them out a little. Note the air pump for the lumbar supports.

Test fit of the new frame. Spot on! All holes lined up perfectly.

Top it off with the foam and the seat begins to take shape.

Now we start installing the upholstery.

Getting ready to stretch and pull and attach the cover.

Finished! It was a perfect fit.

It fits and looks great but I think I have to get accustomed to the color change. Maybe the better comfort and support will make the transition easier. I heard someone describe the old seat as a trampoline.
(Dave, I love the new process for adding photos. It's much easier to post something like this.)
Stayed tuned for part 2...