On 08.09.19 3:19, Larz wrote:
I picked up a surplus yard light called Electripak SV-175M thinking that
it was 175 watts. It uses a mercury vapor bulb, but the bulb inside
appears to be 125 W. Since I want to use 175 W mercury vapor instead,
is it possible to swap out the medium base for mogul base and use the
175 W mercury vapor bulb? It has an H42 ballast, no capacitor. Thank you.

The ballast and supply voltage determine power, so your 175 watt lamp
will not get the power you want to feed it.
Lamp an ballast go together.