When doing the valve covers, there are some measurements and removal of the rocker arms and to disconnect the camshaft sprockets and timing chains from the camshafts. Bolt a dial indicator to the front side of the cylinder head and measure the camshaft end thrust of each camshaft; if they are greater than those indicated above, replace the camshaft or the cylinder head. To dismantle the bearing cap: Turn the bearing cap bolts in the opposite sequence as you tightened doing this in a quarter turn till you can turn them by wrench. Now unbolt the bearing caps and raise the camshaft off the head-be careful not to swap around the camshafts and keep track of the individual parts to make sure they get re-installed on the exact cylinder head again. Do this for the other camshaft again. Always take a visual on the cam lobes and the bearing journals for excessive wearing or signs of overheating and always look for flaking on the hardened surface of each lobe. Camshaft journals diameter and camshaft lobes lift are to be measured and compared with the established standards using a micrometer, if any camshaft diameter is below the stipulated figure then it has to be replaced. Camshaft bearing oil clearance to be checked by cleaning the camshaft bearings, positioning the camshaft(s) in their respective area without use of any lubrication, applying a strip of PlastigageTM to the each journal, engaging the camshaft caps properly, removing the PlastigageTM by tearing it across a predetermined line, and then measuring the crushed width of the PlastigageTM against the scale on the Plastigage If the clearance is too great and any of the journal diameter is not with the standard required, then the camshaft should be replaced; if the journal diameters are standard but the oil clearance is too large then the cylinder head should be replaced. Last of all with equal precaution remove the Plastigage to avoid damaging the journals or bearing surfaces. If the lash adjusters and /or rocker arms was removed, place it back to the exact position, apply moly based engine assembly lubricant to the camshaft lobes and bearing journals,then fit the camshaft(s). Fit the camshaft caps into position, tighten the bolts to the prescribed torque in the manner described above then reassemble in reverse of the procedure above.