Most shops don't want to do the extra setup on a stovebolt block, since there are 4 different main bearing diameters. I'd recommend finding a shop that has more skillful (or less lazy) people. I've line-bored plenty of old Chevy blocks, and it does take some special procedures. It's vital that very little material be removed from the block side of the parting line since setting the crankshaft deeper into the block will cause the timing gear teeth to bottom out. I would usually set up the boring tool to remove only .002" from the block, and .008" from the main bearing caps.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
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