Thanks for the replies. I hadn't thought of using a Dremel, but that seems like a reasonable solution.
But in the end, I decided to go with a standard metal plate, as the wood plate didn't go as well with the body as I had hoped. But who knows, there may be a future project...
And Dan025, I'm always jealous of you guys who have access to proper tools. And double jealous that you really know how to use them - I get by okay with my basic hand tools, but sometimes it takes a looong time to accomplish what I'm sure you could do better in 2 minutes.
drewfx