In my opinion, you should first determne which block you have....look at Don's picture of a roller cam block and then look at your block...are the bosses there or not? If not, your 350HP327 cam is good...it's a good cam for the street. The block is probably a one piece main block so your old flexplate will not fit...you can look at the back of the block and the crank...does the crank have a flange or is it a straight cylinder coming out of the seal area? Anyway, it sounds like you have both flexplates anyway.

The pans are different between a two piece main block and a one piece main block. The one piece main block uses a single, rectangular pan gasket that is nice to change compared to the old stuff. Also, look at the block to see if the fuel pump hole is there...it may not be since later fuel injected engines didnt even have a cam lobe to drive the fuel pump.

The World heads will bolt onto your block so you could freshen up the short block assembly with new rings, etc and would be good to go with little bucks spent (unless there is hidden damage). The engine will have plenty of poop for your daily driving....the World heads will be an improvement over the lo-po truck items.

So...(1) verify what you have, (2) determine its condition with rings, cylinder walls, etc. and (3) decide upon the World heads....do they need a valve job? and (4) have fun driving it. It wont set a National Record but who cares?

Best of luck

mike in tucson