[koates]

If the NOS field windings have not been coated then you could paint them with a good marine varnish. Some were coated with shellac originally. Trial fit them in the generator housing before coating so as to get them in the correct curvature. Once varnished they become somewhat stiff. Armatures should be only coated with the correct high temp varnish and baked in an oven. If you only coat an armature with a normal varnish then it could melt when the armature gets hot during operation and be flung off. I have a FUN PROJECTS round voltage regulator on my 34 Ford 3 brush generator for several years with no problems. The only downside to this is the maximum current is 10 amps, but it works well on a standard early Ford which has no extra electrical items except factory. Some reproduction round cut outs have a small flat semiconductor (diode) inside which would be very marginal in coping with the normal early 1928 to 1938 generator maximum of 15 amps in my opinion. I prefer the larger round alternator type diode which will handle 15 plus amps ok especially if its mounted on a heat sink inside the cover. Those diodes can be purchased as a kit for fitting inside an original Ford cut out. But the best cut out is the original round Ford unit provided it is in good condition. Regards. Kevin.