It is never too early to get a shock by playing with radios and TVs that you get from your nice uncle who owns a radio shop or from the dump so doing it late in life is a win. You have already beaten the odds and survived to your 50's. So I suggest the aluminum chassis like a Hammond 1444-24 which is 8 x 12" x 3" with a front tacked on approach. Start with someting simple with no more than 4 tubes like a 6AG7 or 6J5 driving a 6L6 final modulated by a 6L6 and 12SL7 speech amp. Something like this Stancor 10P.
Mike WU2D
Nice little transmitter, I like how the carbon mic voltage is tapped off the cathode circuit.
http://www.k7jrl.com/pub/manuals/stancor/10p/10P%20Instructions.pdf
