There's a sneaky trick that was used frequently back when most of the vehicles on the road used vacuum wipers. There's usually an open port somewhere on a vacuum motor that allows air into the unit which the vacuum eventually routes to the intake manifold. "tune-up oil" like Wynn's Friction Proofing, Aviex, Casite, etc. was available in small cans, usually 6 ounces. We would attach a piece of vacuum hose to the air inlet port, immerse the other end of the hose into the can, and turn the wipers on. As the solvent/oil got sucked through the vacuum motor, it would clean and lube the internal workings- - - - -no disassembly required. The tuneup oil eventually ended up in the intake manifold, where if served to clean and lube the valve guides.
Something like a kerosene/ATF mix would accomplish the same thing if you can't find a suitable commercial product. Diesel fuel and Marvel Mystery oil might be a good combination, also.
Jerry
