1965 cuda fell in ditch help

Hard to say why it's not revving up now. While you're doing the alternator belt, have a good look around to make sure nothing in jammed into the motor after your venture off road.

On the alternator you should have a mounting bolt top and bottom. On the slant six I think the stationary bolt is on the bottom and the adjuster rod top. The 273 is the other way around.

Loosen both. The stationary just loosen a little. Then you might get something like a wooden broom handle to pry the alternator so the belt tightens up a little. You don't want it too tight, then while you're holding it tight, have a buddy tighten both bolts. When you're done you want to be able to move the belt up and down about a 1/4 of an inch.

There should be some youtube videos out there that will help.