If I remember correctly the 83-84 Firebird 2.8L disc was 9-7/8". I was a bit concerned about the pressure plate diameter and interference with the disc but even though it was close......it's been working for a couple years on a daily basis with no problems.
BTW....the stock Chevy long T.O. bearing and diaphram pressure plate work fine with both the S10 4/6 cylinder T5 transmissions as well as the T5 "z" from behind the 305 V8. Both clutches are controlled with mechanical linkage. Pics in Webshots of truck and hot rod linkage setup.
Dave
