Crankshaft ? for TO-30/Z129

1670 SB FM 53

Any idea if this is a bearing for a stock or reground crank?

Since the crank is still in the engine, I wasn't able to measure the main journals. The back of a main bearing had the following info:

03(0 or 9, couldn't read last digit)
1672 SB FM 24

Any idea if this is a bearing for a stock or reground crank?

If the crank has already been ground .040", can it still be reground again (strength??)? Are bearings available for this size? Has anyone put shim stock (.010", .020") behind an .030" bearing to get the clearances right?

Final questions: The reason for the rebuild is a valve dropped, punched a hole in the head and split a piston in 4 pieces. I got another head and will do a complete valve job with new valves, springs, retainers, etc. I was planning on buying a rebuild kit and replacing all the piston, etc, but since the crank seems (to me) to be so far undersized, I may need a rebuilt crank also. Problem is I need the tractor NOW so I can redress my driveway before it completely washes out into the street. Sorry for the rambling...back to the questions: The top of the pistons (still in the block) have the following info:

7A
22454 H
FRONT --->

Is this a stock bore piston for a Z129 engine? I'm considering temporarily replacing just the one broken piston with a used one and buttoning up the engine with existing bearings. This will give me a chance to get a dozen or so hours into driveway repair. Does anyone have ONE piston in decent shape with the above part numbers they'd be willing to sell me at a reasonable price? I'll probably do a complete rebuild this winter if my finances allow me.

Thanks,

Fran