You will want to split the output from your C-band LNB using a 2 GHZ splitter. Don't use one of the cheaper 900 MHZ models. It would be a good idea to put a DC block on the leg that goes to your digital receiver as well. From there, go into a DiSEqC switch with one split, DC-blocked output from the C-band as well as your output from the Winegard. Take the output from the DiSEqC and run it into the LNB in on your SG-2100 motor. Out from motor to your Pansat receiver.
You will have to set up your Pansat to control the DiSEqC switch depending on which dish you're getting programming from. Polarity on the C-band will still be controlled by your Motorola, which is probably the way you want to keep it for now. No need to connect the Winegard to the Motorola.
There are other ways you might hook everything up, but the above is what I'd do.