Lean burn or not ? And Desmog a T-Quad ??

Agreed, my rule of thumb is 70-80’s models with less ports and no 3/8 bowl vent on the lid. I “think” (disclaimer her as there is always someone who knows more) that pre 76
Before lean burn, there was ported vacuum. After that I think it was a mixed bag as I have an 1980. 9292 that has two ported vacuum fittings.