magnum valve springs?

When contacting Hughes about their Whiplash cams, they seemed to think the .552 lift would clear the guides. Larry Shepard's "How to Modify Your Mopar Magnum V8" says there should be about .650 clearance between the retainer and the guide and recommends no less than .100 clearance, effectively allowing a cam with up to .550 lift-anymore than than and you start grinding the tops off of the guides. Of course, this is with the proper springs set at 1.650 height.