You can "keel" me later

What you smilingly tell someone in a penitent tone before you reveal a (usually fairly minor) piece of unwelcome news, such as that you and he will have to disassemble an entire portion of a device that you're working on because you belatedly noticed/realized that part of it needs to be repaired or altered.

Achmed the Dead Terrorist (assisting Jeff Dunham in assembling a set of metal shelves): What are you doing? I keel you! Why are you taking apart the entire bottom section like that after we labored so long putting in all those screws?!??
Jeff Dunham: Sorry, Achmed --- I realized that we put the wrong shelf in the bottom position; the unit will be sturdier if we use the correct shelf down here. Just bear with me for now, please --- you can "keel" me later, after we're done.