Block out of square

@krazykuda , do know the sequence the block surfaces are machined? If a un-machined casting is set in a jig, what surface is machined first? Is the block removed from the jig and set up in another machine for other operations. My point being, If something was wrong from the start, all the dimensions would be off if the block remained in the same fixture during the process. If the machine shop line bored, square decked and bored the block to correct issues the bellhousing surface was left untouched. Bores and decks are dependent on the pan rails being correct. also the main saddles are used. I am just trying to see where in the process something could have gone wrong.