You can just use a hand drill for lexan though it can take a while. When I drilled my lexan, my panels were already mounted, so I couldn't use a drill press. I used a forstner bit for my button holes, which was SLOOOW. Spade bits would probably work better, just be careful not to push too hard or you'll break through at the end rather than letting the drill do the cutting.
When you have your lexan cut to size, just line it up with your panel, clamp it, and line up the bit carefully centered over the holes in your wood, and drill.
Ideal situation would be to drill the lexan on a drill press.