Motor Question

[Rob]

The `51 parts car I bought For the motor has this # stamped on it 1R129194 is this a `51 ?

I know the motor has been rebuilt because it has 30 over pistons. I think the rod bearings are .001, the # on them is
CB 286 M
M G 60
.001 U.S.

I don`t know about the main bearings, the only #`s I see on them is

FM 9897 S B -This # is on the center 2 bearings
FM 9898 S B - This # is on the rear main bearing
FM 22 - This # is on the front main bearing

Are the main bearings standard?

Thanks for any info you all can give me, ROB

[whacker]

FM 9897 S B -This # is on the center 2 bearings Federal Mogul standard set markings as done about 10 years or so ago
FM 9898 S B - This # is on the rear main bearing
FM 22 - This # is on the front main bearing

[Rob]

So the mains are standard. Good deal.
The motor # 1R129294 Is this a `51 motor, I know it`s not a `50 because of the motor mount location

[Dwain G.]

The engine came out of a pickup truck. Probably a 1952-53 model.