throwout bearing

I put in a 231 inplace of the 225 used adifferent flywheel it's thiner than the one on the 225. Used the throwout bearing from the 225 had to ajust it alot. after about a 1000 miles it gave up. Is there alonger GM bearing I should use or should go back with one for a 225. I'm not sure what the motor came out of but was in a chevy PU got flywheel with it but don't know what it is off of either but is about an 1 inch bigger in dia. the bearing seemed to be in good condition is why I reused it. Any thoughts would be helpful.