Martin Brown formulated on Wednesday :
Hard bit is mounting the thing rigidly onto the wall at a height.
(although it will work fine mounted on the wall at any height provided that
it has a clear line of sight to the geostationary satellite)

True - some of the early dish installers assumed a dish had to be as
high as possible. That is absolutely not the case at all. My dish I
installed at the back, just 6 feet off the ground, after Sky installed
it at the front, hidden from the sat by the house eaves. My first big
steerable dish I installed on the ground.

My 'sat finder', is a rather clever gadget which 'plugs' into the back
/ top edge of the dish. Its plastic, you dial in the sat you want to
find, then a combined compass/ level indicator is just aligned with the
bearing and azimuth marks, by adjusting the dish. The gadget gets me
within a few degrees, just a matter then of fine tweaking to find the
sat.

Beware of trying to use a compass if the dish is a steel one