On a side note, a '62 Bassman is a pretty special amp, it deserves only the best. I'm not sure I'd leave it in the hands of a tech that wants to put Sovteks in it. Are you sure this is the guy that you want working on this amp? I'd be looking for someone who specializes in vintage amp restorations. The amp is worth the extra effort. But that aside, it's kind of a shame to only use it for bass when it makes such a great guitar amp, and there are lots of amps out there that work better for bass. Have you considered selling the Bassman, which should bring in a tidy sum, and buying a bass amp? If you want to stick with a nice vintage amp an Ampeg B18 would be really cool, and IMO better for bass.