Yep, early ZZTop was fantastic; actually even up to the 90's to me.
I remember their Montreux performance in the mid 90's ('97?) with Orange stacks on stage (for looks only I'd guess), killer.
I’d have one of those amps if they actually did the dirt that is on those albums. Great cleans and verb’s but even cranked the breakup isn”t nearly as saturated and raw as a Brown or Tweed Fender gets.
Looks like he was using a 60’s Fender Brownface Deluxe as his core tone. That little old amp getting all that tone. Of course the ‘59 LP doesn’t hurt either
I’ve honestly never been a fan of this ´80 live tone; sounds like a smaller amp pushed too far and/or nasty fuzz to me.
Much prefer the earlier 70’s sound with the big Marshall based rig, or even the later 80’s /early 90’s vibe he had.
The ´90 tour for instance was great: