Motorhome graphics

[Dakotagrafx 7,297]

A lot of RV art is metallic based and hard to duplicate

[Wildgoose 4,200]

My 0.02 is that if it's your own rig then its a great oportunity to advance your skills. At least if you mess something up you can decide if its bad enough to tear off and start over or live with it. I agree with Maddog, I would remove the old stuff (after taking some pics) and then do you best to match the flow of the old graphics but in the end you may or may not match them exactly but who is ever going to know or be able to tell. I too use the picture with an object measured for scale. On something this big I would recomend drawing the graphic at a more normal size, like 48 inches or something and then scaling up so you aren't trying to draw such a big design. If this was something like the door of a pickup it would be different and you could probably just build it right to scale from the get-go but you are going to have 12 foot long graphics or more to be playing around with. Hopefully  your cutting software lets you cut as you go and will cut a few feet at a time before moving on or you may run into tracking issues. My cheap cutter didn't like anything longer than a few feet. I have SignCut Pro that came with my P-Cut and it has an option to cut long graphics in increments that you can dial in. Hopefully Flexi sign (which I think you said you use) does also.