I just went through this last year. Use the double roller chain, roller cam button, new timing cover. The stamped steel cover has way to much flex. Camshaft endplay is a trick to set and needs to be done correctlly. If you want to see my project do a search for "roller cam upgrade" Good luck!!

Thanks folks.
I'm going with the retro and the button. Got to have a double roller chain.

If you would use a quality billet gear and chain setup you wont have the end play issue. Most double row set ups are pretty cheaply made. That is money well spent!!!!

The Rollmaster is the best, but not cheap.