In fact it was written by Merle Travis, composer of many fine songs such as "Dark as a Dungeon," "16 Tons," and "Kinfolks in Carolina," to name a few. He's also the guy who Doc Watson credits with teaching him to fingerpick. Here's the lyrics:

So round so firm so fully packed, that's my gal
So complete from front to back, that's my pal
Toasted by the sun, and I'm a son of a gun
If she don't make my 5 o'clock shadow come around at one
You can bet your boots I'd walk a mile through the snow
Just to see that toothpaste smile they mention on the radio
If you don't think she's a lot of fun
Just ask the man that owns one
So round so firm so fully packed, that's my gal

So round so firm so fully packed, boy, she's for me
She's just like a money-back guarantee
Like the barfly goes for drink, like bobbysoxers go for Frank
And just like Jesse James would go for money in the bank
From head to foot she's a perfect size, she's a whiz
But she wears a 45 gun that is
She's got the look that's so impressin'.
She's got the pause that's so refreshin'.
So round so firm so fully packed, that's my gal


My wife finds this song distasteful, if not offensive. I admit that lines like "Just ask the man that owns one" are not exactly PC, but I can't resist that toothbrush smile and those bobbysoxers goin' for Frank. In addition to Merle's recording, I know that Ricky Skaggs did this song on one of his early albums and I think there may be a Doc Watson recording around somewhere. Also, if you're interested in the chords, drop me a PM.