There is no way you can set the clearance running with the adjuster off the pivot. You can do it on a Chevy because the adjuster doesn't move. Not on a Chrysler.
You can adjust Mopar rockers while running. Use a universal socket on an extension with your ratchet. Been doing all my life.
Just clearance the rockers with a cutting tool or stone. Factory 340 hydraulic rocker arms were clearanced from the factory because of the 1.50 OD valve springs.