headlight sockets

[Badpuppy]

All i've seen is Fig 436 of the FSB, which doesn't tell you more than you already know.

The 1928-E29 H-type headlamps used a different bulb set than the 29-31 Twolite type. The only bulb you will find for the original sockets today is the 21/3 CP, #1158. The others, eg, 50/32 will fit at right angles in the original H sockets. The replacement socket in your pic appears to be made for the later Twolite bulbs.