Have a 50 Chevy short bed in the shop right now that is going the same route as your plans. It's a budget build so the owner bought one of the bare bones MII kits which I think was around $1200. Might snap some pics even though a search will turn up much info as this is a popular project. Lowering blocks will get the rear down but if over two inches I like to add a Panard bar or maybe a sway bar also. Ignore the hype on four link as it's for a huge engine and sticky tires to get hookup to the pavement. NOT ONE PERSON IN 10,000 actually knows how to set a four link for track conditions and wouldn't crawl around under their ride as the track changed even if they did. Your 305 will be just fine and if you want a few more beans GM had the factory parts on some mid-80's IROC Camaros that did the trick.

Evan