Spending a summer on the road with Kiss is clearly rubbing off on Def Leppard.

The two groups are currently in the middle of a co-headlining tour, and by all appearances, they've been getting along swimmingly. Lep guitarist Phil Collen posted a picture of himself in Gene Simmons' Kiss armor, and singer Joe Elliott served as the surprise announcer for Kiss' set on July 26. Collen joined Kiss onstage during their Aug. 2 show, and a few days later, Elliott went on record as saying the current Kiss lineup might be the best one of all.

As you can see in the fan-shot concert footage above, Kiss have even worked their way into the Def Leppard set list. Filmed during their July 23 appearance in Tampa, the clip captures the band slipping a line from the 1976 hit 'Beth' into the tail end of a performance of 'Hysteria.'

So when do we get to hear Kiss covering bits of 'Pour Some Sugar on Me' or 'Photograph'? The ball's in your court, fellas. And with the tour scheduled to end Aug. 31 in Texas, you'd better make your move soon.

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