Numbers Matching

[grumptruck]

So after roughly 30 years of playing with Muscle Cars and knowing how important the correct part numbers can be in verifying the authenticity or correctness of a particular car, Im wondering how this applies to our trucks.
I own a '67 C3500 and it is very original with les than 68k miles on it.

I see numbers everywhere. On the firewall, on the hood, the engine block, the trans and rear diff etc....
While playing under the hood yesterday, cleaning etc, I noticed some numbers on the brake booster - Yellow stamp of BB and some stamped in numbers (not casting) on the master 133 1k It happens to be a 133" wheelbase 1 ton.
Do these numbers correspond or are they just random ....

I'd love to learn if there in fact a way to verify what parts are original to the truck