Well, Dunc, you're rejecting a lot of versions so I'll offer mine for approval (not in any great hope, but it starts off close)

Twas early one morning at the break of the day
The young cocks are crowing the farmer did say
Rise up me young fellows and work with a will
Your horses need summat their bellies to fill

(Chorus) sing toorali oorali oorali-ay
What have you been doing this long summer day
You ain't ploughed an acre I'll swear and I'll vow
For you're damned idle fellows that follow the plough

At four in the morning, we rise from our bed
Go down to the yard and we're dousing our heads
We curry our horse and take them in tow
Cos we're damned clever fellows that follow the plough

At six in the morning it's breakfast time now
And welcome it it I can certainly vow
With eggs and with bread and a bit of old sow
For we're damned hungry fellows that follow the plough

We harness our horses take them to the field
And a plentiful harvest in time it will yield
We plough all our furrows all in a straight row
Cos we're damn clever fellows that follow the plough

And it's come even time then our work it shall end
And it's down to the alehouse to toast an old friend
With a gallon of pint pots all in a straight row
For we're damned thirsty fellows that follow the plough

(Is that any closer? Not from the Watersons, by the way, don't think I've ever heard them sing it, but I've only got one record)