2g 4g63 are not 6 bolt, they all are 7. 1g heads will work on a 7 bolt block, but they are not a direct bolt on, i believe the holes for the studs have to be opened up or changed. compression is different, head and intake manifolds are different, 2gs manifolds, o2 housings, and throttle body elbows flow better stock than 1gs. No cas on 2gs? i believe. someone who likes 2gs chime in. lol, these are some of the things. theres a writeup somewhere about all the differences.

heres whats needed for the swap...


http://tampabay.dsm.org/phpBB/viewtopic.php?t=12481