“Grumpy McFarland”

RORY: Grandpa says I remind him of her [Richard’s mother].
LORELAI: That is the biggest compliment that can be wrenched out of Grumpy McFarland, believe me.

I think Lorelai is making a play on Spanky McFarland, one of the characters from the Little Rascals movies, earlier discussed. He was played by George McFarland, and in the earliest movies when he just a toddler, did have a rather grumpy demeanour.