I won't comment on whether losing 5 lbs is a good idea or not. That's for you to figure out.
One good resource I just came across is in Matt Fitzgerald's "Racing Weight - How to Get Lean for Peak Performances". I would recommend you check it out - it has a lot of good info for endurance athletes specifically about your question.
The two big things I took away from that is, as an endurance athlete that's not hugely overweight, you should try to lose weight by upping your activity level and maintaining calorie intake rather than just calorie restriction. You need proper fuel to maintain your training. More training (running in this case) will send a signal to your body to dump any excess weight (get lean), whereas calorie restriction will send a starvation signal and actually cause your body to slow its metabolism to survive the famine it thinks you're experiencing.
He has a chart on p.99 that simplifies the whole "what should I eat & not eat" question. I'll list it below. Basically it's a point system, and you want to accumulate as many overall points as possible each day. Good stuff raises your score, while bad stuff adds negative points, lowering your score.
Servings
Food 1st 2nd 3rd 4th 5th 6th
Fruit 2 2 2 1 0 0
Vegetable 2 2 2 1 0 0
Lean protein 2 2 1 0 0 -1
Whole grain 2 2 1 0 0 -1
Lowfat dairy 1 1 1 0 -1 -2
Essential fats 2 0 0 0 -1 -1
-------------
Refined grain -1 -1 -2 -2 -2 -2
Sweet -2 -2 -2 -2 -2 -2
Fried food -2 -2 -2 -2 -2 -2
full-fat dairy -1 -1 -2 -2 -2 -2
Fatty protein -1 -1 -2 -2 -2 -2