RE: fm converters
Not sure about the converters.
Sounds like they would be pricey if they are that hard to come by.
here's what I did for my '60 hardtop
1. bought a $110 Pioneer SuperTuner with CD player and installed it in the glove box. The thing has more amps than I'll ever use!
2. bought a $60 pair of Sony speakers and hid one under the passenger seat and one on the firewall behind the radio (sort of wedged it in there with shims). They are only about 4" or so across (3-way speakers) so you can hide them anywhere.
3. hooked up the speakers plus the console speaker to the Pioneer.
Now I can get AM, FM, and listen to the CD of my choice. Didn't touch a thing on my original working radio or amp so it is an easy conversion to get back to original. The original radio still has power to it so it lights up at night.
My Fm has something like 12 or 15 presets which you probably won't have on the conversion.
I really love the CD more than the radio cause I can listen to some REAL music from the era of this automoibile - it's like a time machine when Chuck Berry comes on and I'm driving the Bird!
'60 TBird hardtop
'64 Galaxie convertible