I made a heatshield out of some 1/16" thick steel, then painted it flat black. It's a flat piece that runs along side the starter (between the header) and then has a tab on the bottom with a hole drilled through it. The outside starter bolt goes right through it to hold it in place. I've got about 5 years and 25K miles on this ministarter and shield with no trouble (knock on wood!).
You can kinda see what I made in this pic - look between the header and the engine block.
Another good thing to check would be your battery cables. If they're original, they're 11 years old now and it wouldn't hurt to change them. Make sure all your ground wires are in good shape too.