Pat,
You didn't go into why you wanted to remove the body, its also worth watching the second part of Edd's video which replaces the chassis and puts the body back on the chassis.
You do realise that after Edd and Mike had there hands on it it went back to a Morgan dealer to be rebuilt properly?
As for a guide to chassis replacement? Forget it! Any one who has done the job will tell you that the most important job on a chassis change is to get the crosshead set onto the chassis correctly - get that wrong and you are left with a car which will not steer or handle right but that pair don't give it a mention!
Arwyn