I'm a big guy (6'3", 182 pds.) and i have natural upperbody strength. Do I need to lift weights still, or should I focusing on staying "skinny."
Just because you are naturally big and are a 800m guy this does not exempt you from gaining strength. There is a way you can gain this without bulking up no more than you already are. being 6-3 182, would seem whimpy to do what I do as a 800m guy (5'-10"- 143) ex...when I bench press I usually put on 10 pound plates which totals 55 pounds and do high burnout reps 3 sets of 25 with short recovery.
This will build you strength. Lower body and upper. Your should be plates of 25 plus the bar 50+35=85. 3x25.
Low weight high reps this is the key!
Once in while you can do some heavy stuff!