I'd stick to the spec. And I usually run through them twice. I always do on new engine builds and usually do on service adjustments unless the engine is a complete PITA to run through once. I like running twice to A) double-check my work and B) look for big differences from the first pass to the second that could indicate valvetrain issues. If they're not clear out of whack before adjustment and the clearance stays dead on the second time around, I know everything is hunky-dory as far as valve seating, rocker arm wear, etc. For Dodge pickups, I've got the rotation tool and a 4-foot extension I can usually snake down to it with a universal joint so I can turn the engine over from the top side. The funny thing is that I'm a John Deere technician, and the same rotation tool works in a lot of Deere engines too.