OK, I have a frame I got cheap, but I can't figure out what size headset to put in it.
It's not designed for an integrated headset and the inside diameter of the head tube - as measured by a micrometer - is about 39.3 mm (just a bit under 1 9/16").
What size headset cups would fit? 1 1/8" cups have an outside diameter of 34 mm, 1 1/4" cups are 37 mm, and 1 1/2" cups are 49.6 mm.
FWIW, I have a 1 1/8" fork I'd like to use on the build - since I already have it.