I set mine as follows.
Get the brake shoes sitting flat on the cams, the main shoe is easy and use the adjustable rod to set the second shoe.
This brings both shoes on at once. Then follow Slakewell's method of finding and removing the high spots.
Something else to check is that the backing plate is sitting square to the drum when everything is tightened. One of my backing plates has some corrosion on the area that sits against the fork leg, where the axle runs through. This plate sits very slightly crooked when the axle is tightened but it's fine when lose.
Check the acnchor lug is not binding when you tighten things up. This is especially important when you have mix and match parts.
Finally when you tighten the front axle spin the front wheel forward, pull the brake on hard and while holding the brake on, tighten the axle nut. This should let the backing plate "float" into the most central positiion.
hth
Brent