Still no forward unless S1 and S2 are swapped

[mebucko]

I'm ready to call it quits. I still cannot get forward to work, only reverse. When I swap S1 and S2 leads at the motor, it goes forward, with selector in reverse. The cart (motor) is very jerky when it starts out; almost wants to lift the front wheels off the ground when going forward (reversing S1 and S2 leads for forward), does the same when S1 and S2 are in correct locations and going in reverse.

Bought and just installed quality 4 awg (crimped and soldered) motor wires. I have one question about these wires: the drawing I got from this site (wiring schematic) shows S1 of motor to "B" of fwd/rev switch, and S2 of motor to "D" of fwd/rev switch.

Is "B" on the left of threaded shaft of this switch (looking behind this F/R switch where motor wires attach to) and S2 to "D" is the right threaded shaft of switch?

I tried reversing these two motor leads at the switch, but it did not help, as I can only get reverse part of selector to work; motor goes forward or reverse depending in the S1 and S2 lead connections at motor.

Original and new F/R switch do the same. I disconnected the bar from the F/R switch, and then I manually move the F/R selector until it stops at the bump stop to see if I don't have the F/R floor bracket mis-aligned. No difference. Only reverse selection of the F/R switch works. Solenoid does click though, in both forward and reverse.