There are only 2 bicycle shops within a 50 mile radius of where I live. The first shop I took the partially laced 20" wheel into ... the guy starting hyperventilating and nearly passed out. He is a "new bicycle" only, TREK dealer. He said he hasn't tried to spoke a wheel in over 15 years.
The other bicycle shop owner (and bike mechanic) told me to leave it with him for a day or so ... he would measure the hub and feed the numbers into his calculation program ... and see if we couldn't come up with the correct length spoke. I then told him I'd be back with a similar hub and a 26" rim that we'd have to do the same thing for ... find the correct spoke length. He didn't seem too flustered by the request.
I did order one set of pillow block bearings. I'll use them to drill all 3 rear frames ... and order some more using my next paycheck.
An old riding buddy asked me how much it would cost for me to make him one of these DeltaWolf trikes ...