I just had one done in the beginning of May. I just ate jello and juices and such and bolused for them. It may be a good idea to do some basal testing just to make sure

The prep is unpleasant enough without low bg's! lol And, you can wear the pump during the procedure, or you can take it off. It is only like a half hour that you have it off for, so whatever you feel more comfortable with.
Good luck! Hope all's well!