How difficult is it to assemble a set of bare heads? Are there any special tools I would need?

The only one that comes to mind is a valve spring compressor.
I would recommand one that camps down like a big *** c-clamp. The breaker bar kind are F'in pain unless have them bolted to the block, but that's a different deal ussualy involving just swaping out springs.

Also if the heads don't have threads for the rocker studs, then you either need a press, or you can tapped them for threaded studs.

Ron

Assembling bare heads is very simple as long as you have the right tools. Like Ronterry said, a valve spring compressor is pretty much all you need. The "c" clamp style is the best kind to use. The look like a big pair of vise grips. Just make sure when you are assembling, that you don't forget to put the valve seals on. I did and I had to go back and put them on while the heads were on the car. Pain in the A$$!!!! I hope this helps.

Thanks!

Might also need a valve spring height micrometer to set the proper spring height. Depends on how detailed you want to get.