Dave, could I simply clip the wires from the old mechanical timer, solder and shrink-wrap them to the RF 124 and plug it into the controller board? Could I get that lucky?
That lucky? I doubt it. There are many unanswered questions I think need to be answered to decide what ACT controllers to purchase
What is the control board (which you stated took less than an amp) doing? Does pump, heater, light, power come from the controller? And what is the timer doing? Do you want X10 to run everything in the spa?
What ever the timer is controlling, is it 120V, 240V, both? etc. The specs you provided doesn't say much, i.e. is pin 3 and 5 the heater control? What is the voltage and current of the heater? Same question for the pin 1 and 2 connection and what ever it is controlling. My guess is you will need a RF124 for the 120V and a RF 234 for the 240 V, but without more information I dunno. How comfortable are you with a digital voltmeter and 240 volts?
Additionally, as much as I would like to help Phil Kingery sell you multiple ACT 124s and 234s for total AHP control of spa heater, pumps, lights, etc, I suspect the ACT solution will be more costly that buying a new mechanical timer.