what to say to nit pickers at car shows

Beautiful car and great comeback from your dad.
Have a great Father's Day weekend with him. I lost my dad when I was 7 years old, so enjoy every minute you share!
I love great comebacks like that. Back when I was coaching girls fastpitch softball, I worked with a another coach that had a classic line when arguing with an umpire over a blown call - guaranteed to get him tossed from the game. When the argument was obviously going nowhere (as all arguments with umpires do since they never make mistakes), he'd lower his voice and calmly say to the ump, "You're a better man than I am. 'Cause you can kiss my *** and I can't."
Seems like that could've applied in this situation as well.