[mickmate]

Just go with a mill if there's a lot of holes the same size to be done. A Jancy cutter or annular cutter like they use in the Hougen Broach and Porta mag drills are also good. The other option is straight cutting on an angle and cutting halfway across from the other side on the same angle. As far as the plasma cutter goes I use the flat edge of a framing square as a torch guide for a straight line, I can usually clamp it in place with the ground clamp on shorter cuts. A trammel tool is also very useful for arcs and circles. Don't forget everyones favourite tool the Sharpie!