hey i have another idea....the second time you let it sit, it wasn't that long, (oil gums up the valves) so maybe its can be unstuck...go to an autoparts store and buy you some Marvel Mystery Oil....its a red bottle and i think its for gummed up valves. read the bottle and run it a while see if you can free up one valve and maybe then you can be moveable enough to take it to a shop so you dont have to do so much work yourself (it IS fun tho)....you said it missed before so that may have been just one stuck valve (which will act like a bad plug) maybe it was just sticking some of the time. but doing the work is a lot of trouble (you gotta take pictures and label before you dismantle!!) but you just have to take everything off the top of the engine, then the intake manifold (which hides some head bolts) then the heads come off...make sure you take the bolts out in the right order if you are doing your own valve job, so that you don't warp the heads. if you go to a machine shop, they charge a little for each bad valve, but crack checks and warp fixing is covered in the main charge.
keep me posted! i wanna hear more!