I just got my first k5 (first truck too) it is a '73 with a 350 on turbo 350 tranny, 205 transfer case. questions I have on my transfer case selector from the top L ock L N H H ock what does the ock stand for? the truck also has a edelbrock quadajet carb, I think it is wearing out I am getting the worst gas milage. should I rebuild it or replace it? the truck also has headers and dual exhaust. stock intake manifold, stock air cleaner system, stock cam, 4 in lift and 33.