OT: My Bug Radio Project, more electronics help Options

[McMark]

I'm still struggling with my 56 Bug radio. See my original thread for part I. Tapping into the potentiometer didn't work that great. Well it worked, but it's not very audible. I'm guessing that the radio is meant to drive an 8 ohm speaker (isn't that what a 56 would have had?) and the 4 ohm speaker is therefore quieter.

The front plate on the radio says SAPPHIRE I by Bendix. And if I look up a Sapphire I, it's supposed to be a 6V radio. But hooking it up to 6V doesn't produce anything audible, whereas hooking it to 12V things are definitely audible. Also, the light bulb on the front is bright with 12V and dim with 6V, so at least the bulb is 12V.

What I'm thinking now is that I would like to be able to basically intercept the signal as it heads to the built in amplifier and re-route it to a new 18W amp kit that I would build and install inside the radio housing. That way I could keep the stock appearance, stock tuning knobs, etc and stock functions, but use them to drive a more powerful amp. 18W is more than plenty for the single 4.5" speaker. I might even look for something smaller.

My second option is to use the stock tuning coils, but replace the tuning electronics with something newer. This would also still keep the stock look and functionality but work much better and more cleanly.

Here is a wiring schematic for a Sapphire I. As I've mentioned, I'm not positive that the internals are still Sapphire I, but nothing visually leads me to believe that it's not a Sapphire I. Everything has correct looking patina and everything fits perfectly, whereas I would expect a guts swap to have some mismatch.

Can anyone help me on this crazy project?