Did they ever produce a slant 6 4 speed with a console in 1966?

some guy came by my house once, about 40yrs ago, with a Canadian a-body. My memory is a little fuzzy and I only examined it for about 15min, but it was like half valiant/ half dart.

'63 and '64 Canadian Valiants had Dart bodies (111" wheelbase) with Valiant front clips.

When he popped the hood it had a generator, not an alternator

The alternator was optional in Canada til '63, when it became standard equipment. Chrysler Canada had a contract with Canadian Auto-Lite (i.e., Prestolite) for a certain number of starters, generators, and distributors, and so Canadian-built Slant-6 cars got Auto-Lite starters and distributors through '66, Auto-Lite generators as standard equipment through '62. So that's one example of a specification difference in Canada. Another: the 318 Poly was kept for an extra year in Canada. Another: the 4-speed was available behind the 225 in A-bodies through '66. Another: the carburetor anti-ice system that was standard equipment on US '69s and not available any other year in the US, was optional equipment in Canada from '61 or '62 through '68, standard in '69.

But overall, the Canadian cars weren't behind the US cars, they just sometimes had some specification differences.

and the engine compartment looked like an old valiant/Lancer with the heater box on the firewall.

You're mixing memories. The A-bodies in Canada had exactly the same heater setup as the US A-bodies, year by year. The '60-'62 cars had the heater box on the firewall, the '63-up cars had it under the dash. The '60-'62 Canadian Valiants used Valiant sheetmetal front to back, with only minor badging differences to the US model.