I'd suggest using a narrow piece of steel shim stock like a field-expedient feeler gauge- - - - -maybe a strip about 1/8" wide, for instance. I think I'd look for maybe a maximum of .010" or a bit more?
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!