Bill,
What you nicely describe seems like your engine has adequate lubrication of the rocker arms and around the lifters.
If you want to take the rocker-arm asembly off and clean the insides and holes on the two rocker-arm bars, you will then be certain that it is clear/clean inside, end-to-end.
If you have a low-pressure 235 or a 216, do not expect high pressure (and/or high oil flow) through the assembly. If oil is reaching each rocker-arm and each lifter, it is OK. These engines had an oil-fliow divider/diverter/distributor-valve behind/under the middle of the exhaust manifold. Many Shop Manuals have a drawing of this part of the engine lubrication system.
Soon after the high pressure 235s (and 261s) came out, GM drilled the block so that oil also reached the lifters directly through a journal in the block (assuring enough oil for hydraulic lifters).
