How about a shadow box with pegboard as a backing, and attach the wrenches with very narrow zip ties? They're available in all sorts of colors, to either blend in with the color of the tools, or contrast, whichever you choose. The pegboards will allow you to experiment with a variety of arrangements and mounting positions without scarring up the backing.
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!