Well, your temp gauge is not electric, it is a vapor pressure device. But it
can be replaced with one that is electric from a later Volvo or some other car.
Likewise your oil pressure "sender" is actually a pressure switch that turns
the light on when the pressure gets too low. But you can probably get an oil
pressure gauge that will work OK, either hydromechanical or electric. You
could put in a voltmeter OK. Most later Volvos have tachs that would work as
well on your engine as a later one (which is sometimes not very well).
I think the big problem is to find a good place and way to mount them.
--
George Downs Bartlesville, Heart of the USA!