Here's what I did In my 34 to keep it all period correct. I used an old signalstat 700? Can't remember, but a search will show what I got. So while I liked the old school look, I felt it was too long, stuck out to about the same diameter as the steering wheel. Normally , with front hinged doors, may be OK. With suicide doors , entering from a different angle I thought it looked like a hazard to get your shirt caught on. So, I shortened it up as far as the shape would allow. Very happy with it now.
Next, the old turn signal units require a separate circuit for the signal bulbs as they have no ability to separate the brake lights. UNLESS !! you run power thru a series of relays. The wiring diagram to do this has been posted here many times, I may have it if you wish.
Next you google up "light socket" and thousands of choices come up. I found a 2 terminal socket that only needed a slight modification to fit in the cowl lights, and the rear lights already have 2 terminals. Next, you need a small globe , 2 filament bulb, easy to find at Motorcycle supply houses. Some time and effort required, but far better than some modern looking switch and hardware store plastic lights. JMO. The photos show the shortened switch, and the test panel I used to figger out the wiring. Once done, I mounted a small panel above the kick panel on the drivers side with much more tidy wiring.
So, I still have working cowl lights, with the bright filament for signals