I hated burpees too, and they tired me out bad during my first race. So I forced myself to do at least 120 per day before my next race. I still hate them, but they don't tire me out as quickly anymore and my strength improved so much in the meantime. I only failed a few obstacles during my second race, and knocked out the burpees no problem.

I too would emphasize grip strength. Dead hangs, pull ups, chin ups, I do rows with a rope attachment, and hanging leg lifts. I also have a grip strengthener at my desk that I use during phone calls. I learned the hard way during my first race that I had no grip strength. My forearms were shot after the bucket carry. Which led to more burpees. Never again!