that is part of the fun of building your own car, make this fit here and that fit there.
without pics it's hard to help you out.
i will say this... i found vintage air the most helpful vendor i've dealt with
for the fan sensor i used a piece of ss muffler tube in the lower radiator hose with half of a pipe coupling welded in, it has worked fine for 15000 miles.
there's also thermostat housings with ports in them