73 Marshall Major help

[Music Saves lives]

Thanks for all the responses. Yeah, getting sound from jacks on left and right. Some static and such reguardless of which jacks I plug into. So, when I take to amp tech I will ask him to 1. Change impeedance switch to JCM type or more modern that will not fry transformer. 2. See if the other two jacks are simply phase inverted. and 3. find out what mods were done besides ppimv that seller told me about. Can you all think of any other questions or jobs to have the amp tech do? gotta take a taxi like an hour and a half away so don't want to make two trips! Thanks again.