Drill guide for formed beams

[Frank S]

A project I am working on has a couple of formed beams that need holes drilled consistently matching.
I clamp the formed parts back to back drill the hole than put them face to face and weld them into a hollow open beam
I don't need ultra precision to the nearest tenth but do want them to match within reason.
the simplest way to do this was nothing but a piece of 1/2" plate cut to fit the cavity and drilled with a pilot hole then removed and drill out the hole to 3/4"