Rear mounted Tank with filler in stock location?

[rscam]

I want to put a tank in the rear but my truck is already painted. If I move it I'm stuck with a hole to put an antenna or something in. Has anyone heard of or done a tank move and left the filler in the stock location? It would take alot of plumbing to do but I wouldn't have to come up with something on the rear of my truck. I would just have to run some pipe. I noticed a thread where someone used copper pipe for plumbing. I can do that to!