The circulation pump is definitely the culprit. When I hook up only the circ pump and the digital topside control the GFCI trips.

To confirm that it was the circ pump, I switched hooked it up so that only the main pump and the topside controls were hooked up and the main pump worked great at both high and low speed. So my next step was to hook up the ozonator and the spa light. Things still worked wonderfully. I didn't hook up the heater as I'm pretty sure the circulation pump is responsible for maintaining the water flow past it and I'd prefer not to create another problem for myself by burning it out.

I'm in the process of draining the spa now so I can remove the circulation pump. I guess I'll be ordering a new one

I imagine once I have the pump out I'll have some questions regarding what to order to replace it. But I imagine those questions belong somewhere else on this forum.

Thanks so much for all the help! I couldn't have done it without. I'll be sure and try to snag the new pump from http://spapartsnet.com