This is the version collected by Maud Karpeles from Mr Edwin Ace, Llangennith, Gower, April 18th, 1928, published in the Folk Song journal. I don't have the reference to hand.

Karpeles transcribed the chorus as 'Fol de dol (etc)' - that isn't an invention of the recent folk revival, unless you count Karpeles as 'recent'.

Direction in italics added by me based on local information

The Gower Wassail Song

(First 5 verses sung by wassail party outside the house)
The wassail, the wassail, throughout all this town,
Our cup it is white and our ale it is brown.
Our wassail is made of good ale and cake,
Some nutmeg and ginger, the best we could make.
Chorus                Fol de dol, dol de dol de dol,
                Dol de dol de dol, dol de dol de day,
                Oh sing toorali-o-ay, sing toorali-ay

Our wassail is made of an elberry bough,
Although, my good neighbours, we'll drink unto thou;
Besides all of that, we've apples in store,
Pray let us come in for it's cold by the door.

We know by the moon that we are not too soon,
We know by the stars that we are not too far,
We know by the sky that we are not too high,
And we know by the ground that we are within sound.

Now master and mistress, if you are within,
Pray send out your maid with the lily-white skin,
For to open the door without more delay,
For our time it is precious and we cannot stay.

We're a company designed for to taste of your ale
Out of the kilderkin that's next to the wall.
We want none of your small beer, nor none of your pale,
But out of the kilderkin that's next to the wall.

(Next verse sung by the family from within)
You've brought your jolly wassail which is very well known,
But we can assure you we've as good as your own.
As for your jolly wassail we care not one pin,
But for your sweet company we shall welcome you in.

(Last 2 verses sung by the party on leaving)
Here's a health to old Colley and to her crooked horn,
May God send our master a good crop of corn,
Both barley and wheat and all sorts of grain,
May God send our mistress a long life to reign.

Thanks to our jolly master, thanks to him we will give
And for our jolly wassail as long as we live;
And if we should live to another New Year
Perhaps we may call and see who will live here.
Chorus                Fol de dol, dol de dol de dol
                Dol de dol de dol, dol de dol de day,
                Oh sing tooralioay, sing tooraliay

The song was reportedly widely used in the North Gower villages (Llangennith, Llanmadoc, Cheriton etc). Several slightly different versions of the words were noted by the Victorian rector of Llanmadoc, Rev J D Davies, a keen local historian.

Andrew McKay, Llangennith
Crane Drivin' Music