Be sure to make note of any offset, before you disassemble the wheels.
Lay a straight edge across the brake drum and measure the distance to the rim.
Measure 4 places at 90 deg apart around the rim and use the average.
Assuming a standard cross two pattern, do one side at a time.
Put your inside out spokes in first, then the outside in spokes.
Set the hub inside the rim (somewhat centered), all of these spokes go into the dimples on the rim facing up and are directed at the spoke.
Each pair of spokes (1 inside and 1 outside) will lay nearly straight across from one another and slip through the rim. If the spoke seems to long or to short, you've got the wrong hole. Install a nipple, but only thread it three turns on "all spokes".
Next turn the wheel over and do the same thing, except on this side the inside and outside spokes will point in the opposite direction, from the other side.
When the wheel is all laced up, put it on the truing stand.
Starting at the valve stem hole, tighten the first spoke one turn. Count three spokes and tighten that one one turn.
You'll notice the pattern, your tightening the spoke on the opposite side of the rim as you go.
Once you've gone around the wheel, move to the second spoke from the valve stem and go around again, counting three spokes.
You'll have to go around four times to get all the spokes.
Keep checking your offset as you go.
You will need to loosen all the spokes on one side and tighten the other side to pull the rim over, but loosen and tighten equally to keep the rim true.
Don't try to pull to one side without loosening the other side. You'll end up with spokes to tight.
Once your getting a tight wheel, use a spoke torque to set the final tension.
PS: Make sure to use some oil or anti-sieze on the threads of each spoke. Torque readings will be off otherwise.
Good luck and have fun,
Ron