Hi there. Fellow lefty here. I use to have a Mark VI head and 2x15" BW cab, very nice it was too.
I now use an Ampeg SVT IIP into a QSC amp, then into a Tech Soundsystems 6x10 or Glockenklang 2x12, I sometimes use an Aguilar DB680 pre.
Basses, 1980 Stingray, 2002 Status S2, 1998 Jap Jazz, 1995 Squier Precision and a KGB Status replica.