Not sure what your application is, mentionng a t5, but I do know that all SBF bell housings are NOT the same.
I did a 289 to 351W swap many many years ago and went with the bigger clutch. The smaller housing for the 289 would not fit over the larger clutch/flywheel assembly. I believe it was a 10" for 289 and 11" clutch for the 351.
It is exactly pertaining to my upcoming swap. I have both bell's, the early one that came out from my 68 when it still had the 3+1 OD trans in it, and the newer style, T5 bell housing. I was thinking they are all the same, but then I remembered that a truck application is "shallower" than an automotive application, and that is what prompted me to ask..
hmmm - thought the SBF AT housings were the same - except 64 and earlier, the MT housings are dependent on application..? Don't know for sure though.....things like trucks/BOSS/HD would have had larger clutches....other than that "most" are the same. T5's came in a few flavors didn't they? Might be better info on the Stanger site on that .....
So that means C5Dx is what you need to be carful of and C5xx is common then you move into the D1Tx and it get's tricky again.....even though the flywheel tooth count is the same....jeesh, I wonder why there is any confusion on that subject!:1zhelp: