hey guys just wondering wat the best manual box would be for an XC its got a three spd auto and 250 xflow but im gonna swap that for a mild 351 and was just wondering wat the best one would be. and would i need to beef up the stocko diff to a 9" or will the old one hold up?

you cant go past a top loader for easy bolt in, although so long as the output of the 51's not too high maybe a celica 5 speed would be ok. wheter you need a nine inch or not is entirely up to how you drive it. Where i used to work we had a regular customer who had an xf fairmont ghia with 460/c6 and still ran the standard bw diff