You should probably post this on the Miller board. Most foot controls are similar using a microswitch for on/off and a varistor to control amperage. You should be able to get the owner's manual for the old pedal you have and the one for the Dynasty and compare the wiring diagrams to see the correct pin locations for the wires on the 14 pin connector. All 14 pins will not be used for the foot control, so this should be possible to do.
By MBSims
Date 03-17-2007 17:13
Edited 03-17-2007 17:15
Here's a wiring diagram for a 14-pin RFCS-14 and 6-pin RFCS-6L foot control. The wire colors and connections are the same, but the pin locations are different. If you look at the face of the connector next to the pins, you should see the pin markings (A, B, C, ...).