I bought a lund clear poly bugguard for my new truck, it is supposed to be paintable. It says to paint the inside of the guard, question is is there any prep work or anything that needs to be put on the poly or do you just paint it?

 

Try doing a search. I know I've read some posts regarding this. I think you may need to very lightly sand the inside of the guard so that the paint will adhere properly. I had considered getting a clear guard and painting it silver to match my running boards but ended up going with the standard black/smoke to match the truck.

 

After painting the inside of many r/c car bodies I have found it ok to just wipe the surface with a solvent to slightly etch the plastic
enough to give the paint a toothhold. Only use paint formulated for the particular material you are painting. Mask off the front of the shield with paper and tape(blue scotchguard 3M painter masking, leaves no reside for up to 10 days)so as to avoid getting any solvent on it. Sanding is not the way to go as sometimes the sand scratches will cause a swelling of the paint in even a very minute scratch and then it would be visible from the front. 4/0 steel wool is also ok but you really nead to use a tack rag when you clean up to paint. Hope this helps.