This was sung on at least a couple of occasions by Garcia in 1966. Even though the line "I been down so long it looks like up to me" occurs in many other songs, I suspect this may be a Grateful Dead (probably Garcia) original: I've never found any similar versions by others, and this sounds quite like other early Dead originals.
(1) Alternative: "I can't stand moving but I don't like standing still"
Hard headed lover, won't you please let me stay all night
If you just let me stay, I think everything's all right
With my shoes in my pockets, eyes on the door
Mama won't you give me the key
I been down so long it looks like up to me
I'm afraid of going but I can't stand standing still (note 1)
The hole that I've been in looks more and more like a hill
In a rowboat on the ocean, swept offshore
I started to feel all at sea
I been down so long it looks like up to me
The candyman is standing with his friends outside my door
There's a hole in the circle and I'm [going down in the floor]
Been told many times, but again my friend, the best things in life are free
I been down so long it looks like up to me
[You gotta have plans] please don't forget my name
'Cause the hand that I got just won't let me win the game
If I had plenty of time [...]
[...] looks like I've started to see
I been down so long it looks like up to me