high-five rain-check
What you verbally give your work-buddy when something you're attempting goes right, but you're currently "all yucky-messy" from the dirty/disgusting job you're presently engaged in, and so you don't wanna soil him by actually slapping his still-clean palm (i.e., he's not actually handling the greasy/muddy/gloopy items the way you are, but he's still providing needed assistance; perhaps he's aiming a trouble-light, occasionally actuating switches/buttons and/or operating other controls to test the device you're repairing, holding items like drapes or hoses/cables up out of the way so that you don't accidentally soil/damage them, etc.) with your icky hand. "I'll slap palms wif ya later, Pal, after I get washed up some --- consider yourself high-fived for now!"
A high-five rain-check can be a similar situation to a delayed hug, handshake. back-clap, etc... in all of these instances, you are merely postponing an appreciative/affectionate/encouraging/celebratory gesture until a more appropriate/convenient time. If you strongly wish to have the pleasant action administered right away, however --- such as if you feel that the person deserves immediate reward/gratification because of the exceptional effort/bravery he put out, or if he has to leave shortly --- a proxy-hug can sometimes be an adequate/reasonable option, provided there is an agreeable bystander present whom you can request to "do the honors" in your place.
Five Check
The male version of a Bitch slap.
Get tf out my face before I Five Check yo ass.