I bet I know why an old-fashioned Farm-All tractor had the engine off center?

[JonBailey64]

This was so the farmer could get a better view of the furrows up front to more precisely guide his machine by keeping the front wheel inside the furrow.

Farmers follow furrows religiously in their tractors when working crop fields. 

Am I correct?

International Harvester called it "Culti-Vision" back in its day.

http://www.antiquefarming.com/farmall-A.html

[r3020]

Not so much to keep the wheel in the furrow but to make it easier to see to keep the cultivators from cutting out the row. Used heavily in tobacco production.

[JonBailey64]

Very well.

I knew it had somethng to do with visibility.

[r3020]

Allis Chalmers had the same deal. I grew up on one of these. WD45.

http://www.antiquefarming.com/PDF/PowerBook.pdf