Jas, that altitude meter (or digitial angle meter) has a magnetic base so yes it can just be stuck on the top of the tube and it will be accurate (provided you zero it on a flat horizontal surface before you stick it on - I use my kitchen counter top to zero mine. It will occasionally time out and go to sleep but turning back on will return it to the last leveled startup so it will still be accurate.
Re the azimuth circle, there are heaps of PDF files kicking around here and other forums (like Cloudy Nights) for various sized base circles. You will need to know the diametre of your base to know which one to get. Once you download the file, just take it to any Officeworks, or local printing specialist, and get it printed out in full size (which maybe A1 for large scopes) and then have it laminated. Depending on what sort of base bearing you have you will have to cut the circle to fit around the bearing and then stick it on the ground board with spray contact adhesive. You will need a little indicator marker to point to the degree number on the azimuth circle (I used a nail glued into a small hole I drilled in thepart of the mount that moves.
Just search for setting circles and you will get heaps of info. Not digitial setting circles as that tends to be more about encoders and not azimuth circles. You could search for azimuth circles as well.
Here is Richard's thread on his setting circles, with links to various PDF files of different sizes (just go through the thread until you find one right for you or contact Richard as he cuts files for people (at least I think he still does that). It's worth reading what other people did and look at their photos as it will give you a better idea than my words above.
http://www.iceinspace.com.au/forum/s...etting+circles
Have fun.