Stan wrote:
Using a multimeter, what resistances would I expect to get from a
working H4 car headlight bulb?

Very low indeed, and too low to measure with any accuracy with a normal
multimeter.

Say it's 55 watts at 13.8 volts. Resistance is voltage squared over
power, so 13.8^2 / 55 i.e. about 3.5 ohms when hot. When measuring cold
you can divide that by about 15, so about 0.2 ohm.

HTH
--
Andy