I'm on the eastern arc north of Jackson, TN seems to do pretty well as far as rain fade goes, although I haven't used the western arc at this particular location to really compare which is better.
I believe it will work but, you'll have to run a phone line from the vonage box (may require a splitter depending on how many phone outs are on the box) directly to the receiver. The wiring within the walls of your home aren't going to work anymore.
Just leave it on the 300 dish and change the satellite to the one your trying to check the signal of. I'm not a installer but I'm pretty sure none of the VIP receiver's have a 1000 series dish setting.