91-92 GM 2.8 liter V6 according to google http://www.tonkinonlineparts.com/p/__/TRANSMISSION-Manual-5-Speed/6319361/15965646.html
OK My two cents worth, having done this swap in my model A I believe this is of a s-10 family. s-10 have the shifter tower located right behind top plate, camaros shift tower is located farther on the tail shaft which makes it a lot tougher to get into as model A. Great conversion though. but not much hot rodding going on there.lol
Yup, S10/S15. Forward shift tower, coarse 1" splines. Contrary to popular belief, these are not exactly weak. The manufacture load ratings are not for shock-loads, they are for continuous-duty.
Nice find and perfectly suited for what most of us are building. I wouldn't throw huge HP at it but I am running one in the GMC I am building.