For what it's worth, I did the Holley swap on my '65 305 V-6 and was *very* glad I did as the improvement was dramatic. Personally, I thought the Stromberg/governor set up was crap. Others may like the Stromberg, but I did not and it put a smile on my face to send it to the land fill. As for tuning and set up, I thought it was simple. Sweet and I (mostly Sweet ...) were able to get the Holley set up quickly, easilly. Almost right out of the box.
I can't comment on any merits of the Stromberg as I saw none. My truck ran and drove *vastly* superior after I did this easy upgrade.
You will need to find the adapter plate (I am pretty sure it was the
Mr. Gasket adapter, Part# 720-1937 The Holley 500 swap is an easy project and the improvement is significant and worth the investment. You will need a new air cleaner and you will have some plumbing to do -- both easy stuff, I thought.
Here are a couple of pictures of mine. Not sure the red RTV was a good idea, but it didn't cause an issue... You might be able to get useable info from the picture of the adapter plate. I don't recall having much of an issue finding one -- google it.
Good luck and don't look back. Ditch the Stromberg!
John
