I'm going a similar route with my 70 swinger 340. My car is all numbers matching with no rust, so I'm rebuilding the engine to appear stock. My TurboBuick racing buddy is porting the stock 915 heads aind matching the iron 340 intake manifold. The block is out getting machined and balanced. I picked up a Comp cams roller setup with healthy cam, hydraulic roller rockers, custom pushrods, and adjustable rockers. All external parts(Valve covers, intake, timing cover, etc.) have been sand blasted and repainted Hemi orange. I'm a working joe on a budget, so this won't happen overnight, but I'm an ex=jarhead and a persistent SOB. I'm hoping for low to mid 12's while looking bone stock. Any help or advise would be appreciated. Paul