[Cracker]

WT Cobra - you've got mail!

Regarding the over boring question: 427's had a lot of problems with thin cylinder walls even as brand new blocks - in fact some new blocks even as standard bore were no good or require sleeves due to thin walls. It is widely believed (always exceptions) that 427's are good for up to .30 overbore if everything checks out well.
My side-oiler is currently at .17 over and good to at least .35 after my most recent rebuild. At .05 over per rebuild it should last me a lifetime baring any catostrophic problems.
E-Bay block will not do - but thank you for the lead!