I have a FiberClassic (Andersen, I think) fiberglas Exterior door that has a simulated wood grain. It has never been finished. I was told that I could just stain it to give it the wood-like appearance. I've tried a couple of test areas using an oil based stain (for wood), but I noticed, as I should have expected, there is no penetration. It simply wipes off. Someone suggested using a Gel stain, but wouldn't this react similarly? Any experience with these doors and how to finish them?