i have pre vortec 350 mercruisers 1990,s changeing to new 4 bbl vortec,s.ads all say you just need to change intake and go to electric fuel pump. now i hear i allso need a reverse distributer on the right hand engine. could someone please help me out and let me know if there is any thing else i need to know? they will be hooked to v drives. ive been reading this forum for a few years, you guys are great,this is my first post ,hope i did it right thanks.