Hi Andrew,
I had a 1986 GT5-S with those seats. I can tell you that they are not very comfortable and I always felt like I was sliding around in them.
I have sold 26 pairs of Corvette C-4 seats to Pantera owners and they are very comfortable and they hold you in place even while cornering hard.
I rebuild the frames, reupholster the seats, supply all the hardware and instructions for installation for $650. plus shipping. Look in the parts for sale "search" under corvette seats to read what some other Pantera owners think of my seat or e-mail me at glherrig@yahoo.com.
regards
Gary Herrig
PANTERA INTERNATIONAL
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