Stroker twin turbo

Hi..

im buildin an engine for my 69 cuda. so i decided to do something rear. the donor for this engine is a 360 la or a 360 magum not decidet witch 1 to use. but the idea is to make a stroker 408 (4" stroke and 0.30 over) the turbos kit im using is from www.ssautochrome.com its the firebird 350 tpi kit that i have mashined the headers to fit mopar std bolt heads. no here comes he problems.. the botom part of engine what is the best block for performance use gen1 a or the magnum..And what type of compressor pistons, rods, and crank should i use. cast is light waight but then why H-beem and so on.. ive heard 1k of different ideas. lets figure it out for real.. :cheers: