The little copper exhaust gaskets (that go between the heat exchanger and head) seem like they're practically welded on on one side. Tried picking them out, pulling them out, smashing them out. Nothing of physical abuse works.

Will heating them up with a torch get them out? Will this damage the head?

I had the same problem and made a little tool check out this link: http://www.914world.com/bbs2/index.php?sho...c=50497&hl=

I had a similar problem getting mine out. I used a dremel with a small drill. 1/16 works. I drilled 3 holed in line along the long sides of the copper gasket. Be sure not to drill too deep. Do your best not to hit aluminum. I made a tool that had a 1/16 diameter pin at the end. Something like a snap ring tool. A snap ring tool may even work but I made my own from 1/4 diameter rod and ground the pin at the end. Use this tool to deform the gasket toward the inside. Place the pin in the center hole and pry to the side. By making 3 holes you weaken the gasket and it will bend very easily. Once it is deformed, it is easy to get a hold of it for removal.