I just went through this recently. I upgraded from a SD receiver to an HD receiver and wanted to connect using a single LNB, 18" dish.
Here's what I had to do (beyond the tripod I had to make)
Go into the SD Receiver, Setup.
Go into satellite
Set Dish type to 01 18" Round
Set Switch Type to MultiSwitch (NOT SWM!!!!)
Since you already have a SD receiver, you don't need to change you display to "Display SD Channels" (if you were using an HD box, as I am, I had to make this change.
Some Explanations for you.
Satellite type, that's pretty much self explanatory
Switch Type - Multi Switch tells the Receiver to put voltage on the coax to power the LNB and amplify the signal. If you choose SWM, it requires external power to put power on the coax and drive the amplifier (LNB).
As to setting up the satellite, I created a tripod, that is disassemble - if you want pictures, send me your email and I'll send them directly to you. It's made out of 1-1/4 or 1-1/2" PVC pipe. I put some adjustments on the three legs to level it.
I carry a compass (7.00 at a sporting goods store) and a small level and I can usually get the signal in about 10 minutes or so. If you need instructions, please ask, and I'll be glad to share my knowledge.
I've been to your movie and struggled through what you're going to attempt.
Most important thing you can do:
Use your SD box at home on your home network - then setup your 18" dish at home, using the same box until you get it working. At least that way, you'll be sure it works when you're on the road (assuming you have a clear line of site for the satellite).
Take care,
Josh