I've done all the number crunching--think I'll pull the trigger. Heres what I think the odds are:

15% chance: No valve damage, install new chain, guides, and tensioner and let er rip....

75% chance: Valve impact on right cylinder bank, do the above plus rebuild right head with a couple new valves and let er rip...

10% chance: Valve breakage and cylinder damage. Don't want to think about this to much....but then again, I could use a winter project.......

Anybody else care to make a guess.......