Pete & sheri wrote:

I am making a drilling/tapping block and I need to drill very straight
holes for 8 sizes of taps.

I have some drill/tap guides I picked up at Boeing Surplus. You might
copy the design. These are a clear plastic device with three legs and a
flat surface with a threaded metal insert. The guides screw into this
device. Using these, you make a guide for each desired size. Rough the
insert or use a short bolt. Drill the guide hole, mount between centers
and face the seating surface.

Not much of a description but I could send or post a picture.

Ted