This mod adds two transmissions to the burnside special, that are controlled by a special shift logic, with shift modes "PRNDL". In L, the car drives and shifts like the stock 2/3-speed 'boxes, and nothing is really changed. In D, however, the car will start in 2nd gear, and be locked out of 1st gear, until you shift into L.
A photo is required, so here's the inside of a torque converter:
I give full credit to this mod by @Michaelflat for the idea, hopefully he doesn't mind me improving upon it. Check out his other powertrain mods, they make a world of difference if you drive with a wheel and pedals.