Problem running without rear brake light / turn signals ?

A friend is planning some weekend riding on some VERY tight wood trails. Since I'll most likely be trucking in (too cold in the AM on the highways these days....), I'm thinking about removing my plate, rear brake light and turn signals for the day. Should I expect any weird electrical issues ? I'm guessing not but I don't want to take the stuff off only to have to put it back on last minute.

No, it won't be any problem at all. You may want to cover the open ends of the connectors with tape or some such to keep out dirt/water.
Have a good time! We have some of those ultra tight trails here too, gotta wiggle your bars as you go to clear the brush and saplings away.

Mark