I should've taken some pics

Basically it was on two trestles. One at the front & one at the back.
I supported the very back rear crossmember with a big "tree trunk" log in one corner.
Took the rear trestle out - one of us was holding the other side (unsupported side) at the rear.
The other person lifted up the chassis and swung the arse end round so that it was lined up with the body.
We then took the trunk out of the back corner, and lowered the rear of the body on a plank of wood on the chassis.
We then both lifted the front of the body off the trestle and dropped it onto the chassis.
Much like fitting a car body - lots of shuffling to align the bolts followed.