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.030 is the most you can go for crankshaft journals main or tod right? By the way I found block to replace my cracked one. But it is bored over.060

A 60 overbore on a block isn't wonderful, but stovebolt engines have enough cylinder wall thickness to function with 60 or even 80 thousandths oversize cylinders. The main problem with a big bore block is it limits how many more overhauls the engine can tolerate. Since most of the oldtimers we deal with aren't going to be daily drivers, using a big bore block isn't as much of a concern as it might have been 40 years ago. Just be sure the cooling system and the engine's water jacket is very clean, as big overbores are a little more prone to running hot due to thinner cylinder walls.
Jerry

But .030 is the most you can go right so if you have one already. You would have to find a replacement. For crankshaft journals

Or they can build up the journals and grind back to stock or any other size you select.

Actually, my Federal-Mogul master bearing specification catalog lists stovebolt main bearings down to .060" undersize and rod bearings to 40 under. It's not the smartest thing to do, but the parts do exist. Welding and regrinding a single journal is OK, but trying to build up all the rod or main journals results in lots of warp and the need to do some serious straightening. Even big, expensive cranks like a Cummins diesel seldom got welded and reground on more than one or two journals, at least in the machine shops where I've worked. Passenger car and light truck shafts, no way!
Jerry

Ford has a process that they use on their PowerStroke diesel rebuilds to build up cylinder walls so they're back to standard. There may be a similar process (known as metallizing) for crankshafts, but it has to be expensive. That's the driver for whether it's done much. For large engines where you'd have to wait months for the manufacturer to build you a replacement crank, that would be the way to go.
As far as cylinder oversize, I've seen Model A engines bored 100 over. I think you could even find 125 over pistons back in the day. But the Model A's had pretty thick cylinder walls. Modern engines won't stand nearly as much boring. Not sure where a stovebolt lands in that respect, old time or modern. I kind of classify anything with overhead valves as modern.

I'm in the process of building up a Model A engine with MOPAR 360 V8 4" pistons, which is a .125" overbore. They're a surprisingly close fit, only requiring a smaller wrist pin bushing in the connecting rods to adapt for the smaller-diameter piston pins. The compression height of the pistons is almost exactly the same as the Model A parts. I'm also tinkering with an aluminum insert for the combustion chambers, held into place with an anchor bolt through the spark plug holes, to increase the compression ratio. Just like in the song "Hotrod Lincoln"- - -"A kid in a hopped-up Model A!"
Jerry

I have noticed from the old block 3837004 to the new,one 3836233. The 7004 had a oil passage through the lifter bores and the 6233 does not. I never knew there was a difference. Anyone have a explanation

The block with the oil passageway front to rear through the lifter bores is set up for hydraulic lifters. It can be run either way, solid or hydraulic, while the block without the oil passage is solid lifter only- - - -no way to supply the oil that keeps the lifters pumped up.
Jerry

Quick Digression Boys - Jerry, think you need to start a journal of your Model A project so we can follow along. OK, it's not a stovebolt, but the HiPo crowd can learn a lot, maybe we can make an exception? Here's a goal for you. Next week is the Lone Star Roundup in Austin, Tx. I'll be there, with several hundred other Model A's, and about 2000 Hot Rods +/-. So in a year or 3, suggest you drive your Model A to the Lone Star Roundup.

I'm building this one for an in-law who has a very nice older restoration of a 1930 rumble seat coupe. It's going to be a slightly hot-rodded backup engine with insert rod and main bearings, an overbore, and a high compression head. Stovebolts aren't my only interest- - - -I like Furds, too!
Jerry

Cranks are sent out to specialist and the
Typical quality production crankshaft rebuilder will:

Thermal cleaned
Steel shot blasted
Boltholes and keyways inspected
Worn journals are restored
Bearing journal surfaces are machined, polished
Oil holes chamfered and deburred
Oil line passages cleaned and rust inhibitor applied
Crankshafts are packed and covered with two-mil poly film and encapsulated with sprayed foam
Main and Rod Bearings are included