Roller Rocker Side Clearance

With roller rockers, you should be centering the roller tip on the valve stem. Stock rockers have a veeeeery wide footprint & have plenty of leeway. Not so with a narrow roller tip. Get the tip centered, THEN use shims to position the rocker. You do not need a lot of side clearance, 0.005" each side is fine. Too much side clearance, & the tip can move off centre.