In article yQi1d.262818$sh.77071@fed1read06, Daven Thrice says...

Is there a tolerance that one associates with a line that is supposed to be
visibly straight? I'm going to screw connectors into all of those holes, and
if somebody looks at those connectors, I want them to be in a straight line.

There is another perspective, too. What can I get in terms of accuracy with
a drill press and the tools that Richard Kinch suggested?

When I do stuff like this, I blue the part up around where the holes are
going to go, and use my dial caliper as a scratch gage to scribe a
line a set distance away from the edge of the part. Basically you
just open up the caliper, lock the setting, and place one jaw on
the edge, the other jaw is pressed against the surface of the part
and then you slide it along the edge to make a line.

Then you can use the same caliper to step off the holes.

Once you have the crosses marked out, take a sharp starrett
center punch and carefully pop each intersection. If you
then drill with a sharp pilot drill (I don't bother with
centerdrilling stuff like this) it will pick up the centerpunch
mark nicely.

Then go back and open them all up to 1/4 inch. What are these,
SMA connectors?

Doing it this way will pass the 'looks OK' test but in terms
of numbers, you will be +/- 0.005 inch on location that way
if you practice a few times.

If you need better than that, because it's a production job
being delivered to a customer, then you probably need to
do it on a bridgeport.

Jim


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