Training for 5K Pump and Run

Has anyone on this board competed in a 5k pump and run? This past winter I competed in my third one and benched my bodyweight 14 times (I only weigh 145 lbs) and ran a 5k in 21 minutes. I will be competing in a 5k pump and run at the arnold classic in about 7 months and would like to get my 5k time down to 18 minutes (I used to run a sub 16 minute 5k in college) and bench my bodyweight 20 times. I should also note I am currently trying to bulk up over the next four months and put on 15 - 25 lbs. Does anyone have any tips on how to improve my bench press for an event like this? Last year the first 50 finishers were able to bench their bodyweight 30 times.