advice on 454 build .. 1990 engine

I just aquired a 1990 454 ( complete ) and a turbo 400 trans . all I know is the engine has HP stamped on it and I am being told that it is out of a truck it has the period fuel injection on it and is still as it was when it was pulled . I am looking for advice on a budget build for a stought street motor 500 to 600 hp with a possible shot of spray . I am somewhat new to the BBC scene but have the know how to get it done ( comming from the mopar / import scene ) I have decided that I would try a chev this time . I am looking for something small to put it in ( gremlin / vega / monza /240sx etc ) any and all advice will be greatly appreciated
thanks
Mike

all bbc say hi per or truck/pass and some say truck /marine they all work your engine to make 500 hp .the block crank and rods is about all that i would use and maybe not even the rods or crank i would build it to a 496 they have a better resale for me and not much more$$ if you need any crank work look for better heads less you build for max Tq there many parts you can buy and many ways to build it