Hi, Dave. Boy do I have a cheap and painless solution that works. Bondo automotive filler is great for this. It is available everywhere and made of exterior applications. Just follow the instructions on the can. You can also check their web site which is something like www.bondomarhyde.com or bondomarhide. The only bad news is that it has a short working time so you have to plan your work and be ready to apply it when you mix the two parts. The upside of that is that it does harden ready for sanding quickly.