I wonder if your old altered had a worn out or too short nyloc, we have been using them or a "pinched" nut for over 15 years, because it never seems the cotter pin lines up with the castle nut when we get the right adjustment, spin easy, but not too loose.
As far as lacing and truing your spokes, just find a motorcycle shop that does that kind of work, not all shops do lacing/ truing, I would look for a dirt bike shop rather than a Harley Davidson shop. Also if your spokes are steel, and maybe rusted to the nipples you can only use a bolt cutter to get the hub out, and then replace with new spokes & nipples. Measure the spoke length and dia and Email a picture of your wheels & hubs, so if you need spokes I can send you what you need. Just try to unscrew the spokes from the nipples 1'st. I only use stainless steel spokes and nipples on the wheels I build.
Jon Hansen, jchansen60@gmail,com