I borrowed a friends not so straight edge to have a see if the block was warped.
When I placed it across the block like so, I was able to just push a .003 feeler gauge underneath it between cylinder 1 & 2. I could also fit a .0015 between 3 & 4.
Flipped the thing over, and couldn’t fit anything between any of them, go figure! I checked the block like so, and with the edge flipped back over, I could only fit the gauges underneath between cylinders.
I gave the block a quick clean with a rag and some brake cleaner, this mark still remains between 3 & 4.
Full Size: http://i.imgur.com/HnfPi5r.jpg
So the jury is still out, ha!
Found my camera too, but wont be able to do anything now until next week as I’m away in London all weekend. Plan now is to remove ancillaries from the engine to get it as light as possible to transport it in two pieces to wherever I need to take it. Going to speak with another local machine shop tomorrow and see if they’ll give it all a once over before I or they dismantle it.