You're probably going to fight the job a little bit, no matter what size guidebushing you have. I run some Tsugami SS32's and I've had bar stock similar to what you're explaining. You should be okay, but you're looking at an .0008" difference between guide bushing and bar stock. If it's a long running job you may have some problems because your guide bushing is going to actually be over-tightened to compensate for the .0008". Personally, I wouldn't run it like that.
I like to have my barstock ground +/- .0005" of the guide bushing diameter. I've ran some very complicated jobs with ground bars +/- .0005" with no problems. I pull in and out of the guide bushing 5+ times during one cycle and I don't have any problems. BUT, i've ran the same job with not-ground stock and a difference of .0003"-.001" from guide bushing to stock and the job simply wouldn't run.
You may be okay, but you may have some serious issues. Good Luck!
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