Fun with an old South Bend 13"
I thought I'd do my best to document the markings I found along the way. Some of these pictures are duplicates from above.
I'm sure you'll also notice I decided to do this while in process, as the pictures are from various stages of re-finishing.

S/N - righthand,near side of the bed:
Rack S/N - righthand, upper face:
(Seen on bed w/ bed S/N)

misc. marking - righthand, upper face:

I'm not sure what BB stands for, but it seems to mean "tail stock side".  As has been my experience with older machines, the markings make it hard to screw things up. 
Bearing Assemblys:

Bearing Cap Small:

Bearing Cap Large:
Spindle Thrust Collar -> BB again:
Bull Gear, on the spindle -> &11:
Spindle Cone Bull Gear lockup pt-> Zero:
Spindle Cone Bull Gear lockup pt-> Homemade?:

Spindle Cone matching two -> M's:

Gear Cover Pivot -> 13-147:

Gear Cover -> 13-143:

Spindle Gear Covers -> 13-148 13-149:
Back Gear Lever -> Y:

Drive Mount Arm -> L24:

Rocker Body -> 10-L TP N. S.:
Sliding Plate -> 13 S.M.P: