David;
I have removed the engine and transmission from a 50 ford, 49 MGTC , 72 MGB GT and from my 70 Jag 2+2. All were removed from above except the Jag. I lowered the Jag engine and transmission to a dolly below and raised the front of the car to roll the engine out from under. Did it by myself and it could not have been easier. Nothing beats having 1000 pounds close to the ground and not 5 feet in the air on the end of a cherry picker. The engine does have to be stripped first, exhaust and intake manifolds and motor mount brackets.
I know this does not meet your criteria of having removed engines both ways but I see no reason why I would ever remove the Jag engine from the top. Now if I had a electric hoist on a movable A frame the answer may be different.
Regards, Joel.