I asked for these lyrics last year and Wolfgang pointed to a link which had them from whence I've cut 'n' pasted these, hope it's formatted OK.
As sung in the UK by Johnny Duncan and the Bluegrass boys, (and Bud & Travis in the US) not by St Lonnie as I had misremembered.

SAN FERNANDO

It's the last train to San Fernando
The last train to San Fernando
And if you miss this one
There'll never be another one
So let's bitty-bitty boom-boom
To San Fernando

Last night I met sweet Dorothy
Said, "Tomorrow I am joining in matrimony."
("Do it now, John!")
She said, "If you act right
You can take me out tonight
And we'll wine and dine but be back on time."

It's the last train to San Fernando
It's the last train to San Fernando
And if you miss this one
There'll never be another one
So let's bitty-bitty boom-boom
To San Fernando

Said, "I'm marrying right into society
Be careful of the place you are taking me
Because if you slip, I'll slide
And I'll never get to be a bride."
And we'll bitty-bitty boom-boom to San Fernando
("What is this?")

It's the last train to San Fernando
("Bitty-bitty-bitty!")
Last train to San Fernando
And if you miss this one
There'll never be another one
So let's bitty-bitty boom-boom
To San Fernando

("Sing it, Keely!")
Diplomatically, I asked Dorothy to dance
("How else?")
There was nothing on my mind but romance
I said to myself, "Oooh boy
Better beat this iron while it's hot."
And we'll bitty-bitty boom-boom to San Fernando

It's the last train to San Fernando
("Hush-a-baby!")
Last train to San Fernando
And if you miss this one
There'll never be another one
So let's bitty-bitty boom-boom
To San Fernando

It's the last train to San Fernando
The last train to San Fernando
(quiet)

Let's bitty-bitty boom-boom to San Fernando!
(loud)
Roger the <==0==>