Find neutral on the hockey stick coming out of the nose cone.
Rotate left or right and push in to find either 2nd or 3rd gear.
Rotate the tranny input shaft clockwise (same as engine rotation) while someone watches the rotation of either axle.
If it has been modified for a Spyder (flipped ring and pinion) then rotating the input shaft clockwise gives you clockwise (passenger side) and counter clockwise (driver side) Assuming that the engine is in front of the transaxle.
If the driver's side rotates Clockwise/passenger counter clockwise, then it has not been modified.
You should be able to fit a beefy 1/2" drive drill onto the input shaft to slowly spin it or gently grasp it with a belt wrench. As a last resort, use some 10" vise grips but clamp some rubber between the teeth and the shaft to avoid marring it.