Hi Rod
My setup is identical to yours except I have a 150mm Mak Skywatcher. On advice from this site I bought a QHY5 (QGuider) CMOS mono camera for guiding. This a small camera which has the advantage in having a guiding port that can be connected directly to your HEQ5Pro instead of the complication of going through your computer. I use it with an old 100mm converted Mak telephoto scope at f6 which works well for guiding. It also works well with my Meade 80mm f6 refractor. The free PHD guiding program can also be used as it is compatible with the QHY5.
For details of the QHY5 go to the following address.
http://web.aanet.com.au/gama
If you use this camera focus it carefully and use the dark frame facility to get the best results.
Cheers Peter