Re: you can barely turn the undriven wheels by hand
I'm sorry but you've obviously tightened the nut a bit too tight. I've built, and rebuilt, many vehicles starting with a '51 Willy's 4-73 pickup and at no time have I ever had an undriven wheel not spin freely for many revolutions after repacking the bearings and reinstalling the wheel.
As a rule of thumb, as much as I hate that term, the bearing only need be tight enough to prevent off-axis motion so I'm thinking go a half a turn, depending on where the castle nut lines up with the hole, beyond where it obviously seats but no more or snug it up and back off a half a turn, either way should get you in a reasonable ballpark.
I'm sure there may be manuals that say tighten to "X" ft-lbs, but that's largely shite if you think about it since there is no way they can know the exact taper of the conical bearing, nominal maybe but exact never. You tell me, what's the derivative of the sine of the bearing angle? Yeah, approximations are ok but certainly not gospel.
On a similar note, I'll add that the author misses what is to me an obvious point. The wheels, given their contribution to the acceleration of the vehicle - a wheel / tire combination that has a larger portion of the mass on the perimeter is harder to accelerate than an equal mass wheel / tire combination where the mass in concentrated in the center.
More often than not the latest fad is to have a large diameter, low mass rim paired with a large diameter tire and it doesn't optimize the acceleration since a smaller wheel with a larger sidewall may, actually more often than not, provide a better moment of inertia and therefore less work to accelerate to a given velocity.