Help with a mystery vintage amp head

No. The jacks and the pots are used to set the bias on the power tubes. It requires that the 1/4" plug be connected to a meter; without seeing the circuit closer I can't say if it would be set to DC volts are DC amps, but in the end you set the meter to the right reading using the pots. Both tubes would be set to the same value. Depending on the power tube the correct value shouldn't be hard to sort out.
BTW this amp is really off topic on this particular forum. I suspect you might find better luck- maybe someone might have even seen it before over on DIYaudio.com. They have a section devoted entirely to musical instruments.

It'll probably be great for blues.
But if the restoration goes well then it might sound a lot like a Fender with better low end. This is just based on the size of the output transformer.

That's an instrument amplifier.

I would not try to run it until the filter capacitors have been replaced. This amp was probably made in the mid 1950s.