LT-1 Plug Wire Length

I installed an LT-1 in a Cobra Kit Car and found that the some of the plug wires are too long. Does anyone know of a good set of wires I can make to custom lengths? Most importantly, if I change the lengths of the original plug wires, is the engine going to run different? One more question, who makes good wire looms for LT1s with headers?

Thanks for any input,
John