Wha-hey! Result! Thanks for that link nutty. I have made soem additions and post them here for comment. Unclear Caddick-ese is phonetically spelled and framed in query marks...

Rainbow Waistcoat (© Bill Caddick, 1995)

Mister Isambard he says to me:
Get down ¿Dan? and let your daddy in
"Go and build me a railway to the sea"
Down on the Western Railway

Well if the ¿shant? is good and the wages well
Get down ¿Dan? and let your daddy in
Then I'll build you a railway down to hell
Down on the Western Railway

Blasting, building, tunneling away
Get down ¿Dan? and let your daddy in
Twenty tons of dirt in a day
Down on the Western Railway

But if you dig that ¿lip? just a little to tall
Get down ¿Dan? and let your daddy in
You'll be buried deep 'neath the ¿ship and the? fall
Down on the Western Railway

? sound ? we let the ?
Get down ¿Dan? and let your daddy in
A blackbird died 'neath the barrow runs
Down on the Western Railway

It's fifteen shilling for a sealskin cap
Get down ¿Dan? and let your daddy in
And a rainbow waistcoat on your back
Down on the Western Railway

Tribes of Israel on the track
Get down ¿Dan? and let your daddy in
At the end of the line the ?
Down on the Western Railway

Don't go on a ? pay
Get down ¿Dan? and let your daddy in
I won't come back till the Judgement day
Down on the Western Railway

Mister Isambard he says to me:
Get down ¿Dan? and let your daddy in
"Go and build me a railway to the sea"
Down on the Western Railway

Well if the ¿shant? is good and the wages well
Get down ¿Dan? and let your daddy in
Then I'll build you a railway down to hell
Down on the Western Railway

When the westbound train drive through your land
Get down ¿Dan? and let your daddy in
Raise a glass to a happy man
Down on the Western Railway