Yes, the spacers are to help keep correct valvetrain geometry.
To tell if it's been milled enough to worry about using stand spacers, there is a triangular area right under the middle intake port. If this is gone, then you should consider shims. If its still there, don't sweat it. If you don't need to shim the stands, then you aren't going to need to worry about the head bolts. A set of hardened washers is alot cheaper than new head bolts. .060" off is the max for the later 235/261 engines, and usually requires recessing the intake valve and shimming the valve spring a like amount to prevent the valve from hitting the piston, especially when using a high lift camshaft.
My '55 factory shop manual says 90-95 lbs. on the mains, but my '61 Motors says 100-110. Be sure to chase all of the threads before assembly and oil threads. No sealant required. I went with 90 on mine. Studding the mains is not a bad idea, either.
You should know the year of the engine because I believe the '54's were using shims on the mains, which might mean different torque specs.
