Slightly more involved swap

If only the main driver was swapped end for end, whichever side is last to have the rods put up will find the main crank 180 degrees out.....
Similar event occurred with Hawaii Railway #5 when it was rebuilt in the late '60s by Scenic Railways. The first time they ran it, it went opposite to the direction of the reverse lever.
A guy stopped in at Grove Farm when we were rebuilding "KAIPU" that was there that day and related the story about how HE crawled between the frame (Stephenson valve gear) and swapped both pairs of eccentric blades top for bottom. It ran...... but was lame as a one legged goose.
I though, am personally NOT WITHOUT SIN....
The first time we ran "KAIPU", I pulled the throttle and it went forward.... and then backward... and then forward.... and then backward about 5 times. After I recovered from being awestruck by my newly discovered valve timing sequence that I had already labeled "the Yo-Yo effect"....(dramatic pause) we shoved it over the pit and found the firemans set of blades installed top for bottom. Truly embarrassing with the press there for the historic event.