I have modified the mount and will be installing the waveguide as soon as this rain in the city stops.
My waveguide will then be able to be accurately down tilted for my house (of course) but should get a lot of the city side as well.
I need to get on my roof and see if the new patch antenna suitably illuminates my sat dish - if so it is a very cheap and reliable dish feed.
(For those who didn't know, I was getting an awesome receive signal with a 90cm dish however the cantenna was only illuminating a small area of the dish so it had very low transmit gain)

Wish me luck...