I love your build so far. Have you considered using threaded inserts (see here) rather than T-nuts? T-Nuts are designed to be on the other side of the wood where tightening will pull them into the wood. The way you have them installed they will tend to pull out as you tighten the bolt. Threaded...
I know it's late in the game but I saw this on youtube and thought something like this would be an amazing front end for your bike (play should start at 6:00 minutes):
This looks like a cool build. I've seen everything from precise restorations to wild customs in previous build offs so as far as I understand anything goes. I have already learned a few things from your build so I personally would like to encourage you to continue building and posting on this...
I did a little googling. It uses a Stronglight 49 crank which has a very small bolt circle that holds the spider in place. The spider would have been replaced with custom machined flanges. It looks fantastic but I agree with everyone else regarding it's practicality.
I see one on the road near me occasionally. I hate it, it can't travel in a straight line, it weaves back and forth a foot or so with every stroke. It's a little unnerving to try to pass safely.
I'm probably late too but I found these banjo fittings on ebay. The are like the fittings @HuffnPuff posted. The are compatible a number of different brakes according to the vendor.
Yellow never covers very well, especially gloss yellow. A wet coat of the gloss tends to pull away from edges letting the base color show through. As it stands you could try applying a couple of thin tack coats of the yellow over the current paint. Spray it from a distance so the paint goes on...
It'll be OK. If anything, play up the roughness a little. Make it look like 53 years of use and curb rash. A dark wash, to highlight the scratches and shadows would probably help.
Any idea what this is? It's posted locally for $125 CDN. The color is giving me pause but if it's a reasonable bike I might try to do something with it.
I like this as a girls bike, I'd somehow mount a shortie chrome fender in tight with the front wheel and call it done. On the other hand, what you have done with your original convertible tank is pretty impressive so I'll keep watching.
You may still need the tensioner. With the suspension pivot between your chainwheel and the jack shaft the length of your chain line will change as the swing arm moves. It's not going to change by a lot but I would check out your chain slack at maximum suspension deflection before you discard...