Outdoor Sign Finish that can be easily repaired in the Future

I am completing an outdoor sign that is to be attached to a vehicle. They were adamant it be built out of wood. I am looking for an opinion what to use for the finish? I am leaning towards a simple oil based finish that can easily be repaired in the future. I thought of poly film finishes or an epoxy finish, but the downside is that in two years when the finish fails it will need to be removed. I doubt they will do that, but I am sure they can clean it and apply a new coat of oil finish in the future. Suggestions?

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If you want repairability, your only potential option is a penetrating exterior oil like Sikkens. I hope you made no long term appearance guarantees on this. Most signmakers do faux wood these days and use high quality waterborne paints like PPG to make refinishing easier and much farther into the future.

Thanks Jim. I thought of sikkens and may do a test or two with it. I explained the reality of the finish. Wood was not my preference given the amount of work to build this.

Hope they like grey because that’s what they are going to get.

Some is being stained grey. You know some still want wood doors and have to deal with re-finishing. :D

Yea, customers... LOL