-I have a .pdf file with all the charts you need and a route with helpful hints I've mapped out. PM me your email and I will send it to you.
-A big help: Don't cut corners. The delta can be extremely shallow outside of the channel. You can go from 40ft to 4 ft in a couple of boat lengths. The very experienced boats know where they can cut corners. You will likely see several boats aground. And the tide is usually falling for the 4th quarter of the day so you will have a very long night if you go aground. If you have another boat ahead of you that is cutting corners (usually a Moore 24 or Express 24), then you can follow them.
-It's annoying but there are many, many boats that grossly violate the restricted areas at Port Chicago and are never protested. 1500ft is a very long way and I'd guess that 75% of the boats violate this restriction. Some by 1400ft.
-I put the motor in a large plastic 'under the bed' container you can get from WalMart and lash it to the pole under the mast. If the wind is forecasted to blow 15+knts, lash it under the cockpit to keep the bow light so you can get on a plane faster.
-PHRF ratings are judged locally. It is 144 in most places. In Lake Michigan it's an awesome 159. I think 144 is generally fair, depending on the breeze. The Delta Ditch does not favor the U20 because there is so much dead-down-wind sailing. If you get favorable breeze, I think you can be competitive. It's a great time to improve your deep downwind sailing skills and learn some tricks for sailing low. Either way, it's hours of downwind sailing.
-There are lots of logistic involved with non-sailing stuff: getting the boat back, getting your trailer to Sacramento (assuming you are not sailing back... which is miserable), ramp vs. hoist pull-out, camping, etc. Let me know if you need help.
-It's a very long day. Very long. Bring beer and food. Also bring a good attitude. It can be an exhilarating blast but if the wind is light and you are in hour 8+, it becomes tiring. Either way, it's a great experience.