Let me add some to Roger's post (also like Rocky Hinge Co)

There are actually a couple of different size bear claw latches plus some variations. One with a single rotor which is generally used for light duty and trunk releases. I have the light duty version on my '31 simply because the roadster door just is not thick enough to use the larger two rotor version.

Then, these, regardless of manufacturer, will require a fair amount of fabrication. Not difficult, but time consuming and probably more so on an original '37 door. But, with that said, if you are going to 'shave' the handles, no more difficult.

I believe that Rocky has an integral solenoid version - all you would have to do is hook up either a remote push button switch or a key fob radio version. I have an unused Autoloc one of those that I keep dragging out trying to figure where I can use it - and it is for sale (no solenoids) and reasonably priced.