I used a 9-volt battery at first to perform a range check, and it swings through the entire range unobstructed. I then hooked up wires to my car battery to see how fast the trim responds (the electric trim motor's instructions said to try this, I'm not really insane). It swings a bit faster, but it's still nice and slow. This is good, because I've heard stories about electric trim being too sensitive. There's no way this one will be too sensitive, since it moves nice and slow. A one-second application moves it maybe one or two degrees. Anyway, I hooked it up to an ammeter, and saw that it drew 220 milliamps while operating. Just wanted to get a round current figure to confirm which circuit breaker I should use.
Here's a picture showing the inspection panel and the trim hardware in place. The wire you see dangling out beneath is a temporary extension of the trim motor leads. That's what I used to test this sucker.