What do you think about doing a swap? Is it feasable? Cost effective? Performance effective? If it is a good idea, what are some specs to have the heads built to? Is an RV cam the way to go while I got it opened up?
You will need to convert to 1/2 inch head bolts or get a set of washers that are made for this purpose. I think that I have a set of the old big valve 351 heads that I was going to do this with. If you are interested in these heads let me know and I will look for them.
What KBJEEP says is true you just need the washers. Becarefull what you swap with though allot of W heads aren't any better. If you don't know what you are getting you could end up with some small valve big chamber smog heads. You could probbaly find a good set of E7 heads off a HO 302. These are very common and a good performing head. You could also search the net and look for a set of iron world products, or GT40's. I have seen used ones go for 450-600 bucks.
I found a set of early 80's big valve open chamber cast iron ones for $15.00. The stamps on the heads are d80e and 4d4. That is all I know at this point, I guess once I get with the machine shop I can figure out exactly how good and what I can get them to do for me.