Antenna Mast Advice

[Hoodoo]

I need some advice on purchasing an antenna mast. For reference, I have a Winegard HD7084P. Below is a pic of what I am thinking of doing and I just would like some advice from those with more experience.

The red block is my chimney, the blue squares are the "bolt in" bracket locations and the black is the mast.



I also need to know what to use for the antenna. I originally looked into galvanized steel pipe. Lowes has a 10' max length for around $25. The local plumbing supply store has a 21' for $120... not sure why the drastic cost difference with only double the length.

I am really green with all this stuff but I am very anxious to get this antenna up and out of my garage. Any advice would be appreciated. Thanks.

[tigerbangs]

As for masting: Radio Shack has excellent antenna masting in 5' and 10' lengths: it's the most convenient way to get masting. You can strap to the chimney using antenna chimney straps, which are also available from Radio Shack, as long as your chimney is in good condition. The HD-7084P is a large antenna, so it must be securely atached to whate=ver is going to hold it.
Have a look at this installation guide: it can help you with your decision.
http://www.channelmasterintl.com/docume ... lation.pdf