904 in the wagon took a dump, any help to be had?

Howdy all. I was out for an afternoon jaunt today, and the trans in my 72 Coronet wagon just plain stopped working. The only oddity was about halfway through the drive I was getting on the freeway and stepped on it mildly to get up to speed. There was a small hesitation and a little surge/delay, and then all was moving as normal. About 10 miles later I was at a stop light, and when the light went green the car just plain would not move. Not forward, not backward. I had to call a buddy to bring his truck and drag me the last two miles home.

I have had no issues with this trans to date, with a couple hundred miles on it since I bought it. I do not have any leaks. The trans fluid is full, clear red, and does not smell burnt. Haha, I'm hoping there is a quick and easy solution for what's going on, does anyone have any ideas? I am prepared for the idea it needs major help and a rebuild/upgrade may be in order.

I am completely clueless with automatic transmissions, and to complicate matters the lift in my shop is tied up with my truck at the moment. (Note to self, you will be getting your butt in gear to wrap up the truck and free the lift even though that will take at least a few days.)