Some people can brake anything. My 1965 mustang came with a iron T10 289 2 barrel carb . Added lots of power including nitrous. Lots of street use and dragstrip use on slicks. Never broke it. Bought a new Richmond gear 5 speed. Broke it the first pass. Box it came in said bullet proof transmission.
The 1963 galaxie T10 that comes behind a 390 had a shorter input shaft than one from a 289. A 390 tranny can be used with a longer pilot bearing.
Galaxie T10's are cheep if you look in the right places. I just saw a couple in the last month for $200 or less. Guys that specialize in trannys think they have gold bars in them. I am talking iron cases not light weight galaxie transmissions.
Here is an iron one.
