It's only 60+ feet to the tip so would need to be scaled up a bit for your 100 footer but here's my efforts. Didn't have a MIG at the time so had to make do with a 235 Amp Marquette buzz-box. The thing has stood some 100+ MPH winds with the good sized beam antenna on top. Needs a coat of paint, and as many towers, it gets used as a storage place for some things. May give you some ideas though

This is the base section with the hinge at about the 16' level. CB antenna and tower are just being stored against the bottom of the tower.

Here's a closer shot of the hand winch and cable sheave. Notice the safety chain looped around the bottom of the tower and the upright winch brace.

The tower and parking stand for use while working on the antenna.