need a motor now
I would go with either an AI package or a LE package. might as well do a 383 stroker while you're at it. both companies have several packages putting well over 400 to the rear, but still retain good driveability. i plan on going LE2 this winter myself
If going the budget route I would strongly suggest you put a junkyard shortblock in it before a $2500 or cheaper stroker. Lots of people putting together "built" motors that perform worse than it would have on a stock shortblock and a surprising number of them actually blowing up sooner than a stock shortblock would have.

