heavy engine braking & cheetah VB

You sure you aren't shifting from 3rd to 2nd as opposed to 1st to 2nd?

Put shifter into first detent after neutral, move the car a few feet, and stop

Put shifter all the way BACK (where 1st "used" to be) and move the car a few feet.

You'll quickly see which is first gear.

Next, put the shifter into second and do a drive off from a dead stop, does it move OK?