tune-up problem

[asickber]

My truck was due for a little work so I replaced the fuel lines/filters, plugs/wires, fixed an exhaust leak, and changed the oil. It runs much better when it's warmed up, but when first started it runs very rough. It seems to be getting enough gas, but the engine really shakes the truck. Also when I give it gas the lights get brighter and when I let off they get more dim. Is that normal?

Any advice on what to look at first?