Green’s Dictionary of Slang

bungfungered adj.

(US) confused.

1836		T. Haliburton Clockmaker I 166: Well, father, I thought he’d a fainted too, he was so struck all of a heap, he was completely bung fungered.
1840		T. Haliburton Clockmaker III 70: He was so bungfungered he couldn’t speak.