Back in the early 90's I bought a old 1975 GMT 150w head from a buddy then presided to take it all apart & put the guts into a dead 3 space power amp case I had.
I'm sure some of you think this was a stupid move & I would agree with you at this point but at the time I thought it was the thing to do. Of course I didn't realize it was a pretty rare amp even then ... to make matters worse the original case got destroyed in a fire so there is no going back at this point.
Back then I had a pair of custom made 115 cabs that mated very well with this amp & it would get stunningly loud for a amp rated at only 150 watts & it sounded great as well. I played the crap out of this amp for a year then one night at rehearsal it went up in smoke literally.
I was so busy at the time I just got another rig & moved on. I packed the GK away & forgot about it for over a decade.
Recently I rediscover it & got it fixed ... the power transistor socket had cracked & overloaded a resistor... that's what smoked that night way back when.
I'll be using it in a duo I'm playing in & have it mated to a 210 cab w/tweeter ... The thing sound amazing IMHO.
They don't make amps like this anymore!