For the kick down cable you can buy or make a bracket that uses the carb mounting studs.
I think you should consider an overdrive tranny like a 200-4R with a lockup convertor. You need to reduce the cruise rpm to get max mileage. This brings on a second problem in that the dist adv curve may not be giving you all the adv you need if you have the thing cruising at 1800 to 2200 rpm. You can play with limiters on the vac adv can but you can get pinging in certain situations.
I did a lot of recurve dists in the day but never with OD trannies. It would be an interesting experience.
