I think I have the T-5 that has the 4.03 first gear,it came from behind a 2.8 and I did have to cut another hole in the floor behind the original hole which got welded up. I would like to hear from those who put a T-5 behind a 216 before I would install it,if it works out and the 216 will be available I will grab it but use it for another project. I really like how it runs with the present 235 and doubt I would like less power so the 60 235 will most likely go in unless I run across a running 303 or 324 Olds and hydramatic then the thought of a six goes out the window.