Hi Mick - I have an earlier version of that tripod (I think the legs are still the same construction). I'd agree with the others that it may be putting a little too much weight on it other than for fast exposures. Guess it depends on how you want to use it.
You can hang the combo over the side with a piece of wood attached to the top plate like this Rob Nabholz arrangement (using a different head):
http://www.homebuiltastronomy.com/st...dification.htm
I've used that arrangement quite successfully for visual use with 80 and 100mm scopes, but not for photography.
Andrew