I know of one late 70's K-30 Dually locally that has had a 7.3 turbo diesel & Ford automatic transplanted into it..met the owner at the salvage yard when he was picking out the engine & trans he wanted to buy and put in it..
He said the dually had a 6.2 put in it before he bought it and he was never really happy with it--lack of power to tow and fear of the crank breaking was a worry,and he had several fleet trucks at his work he drives daily with 7.3's and said despite them being "Ford",he liked them a lot and knew IHC actually designed the engine..said he's a Chevy guy,and balked at using Ford "anything",but he didn't like the truck the way it was..
Saw him a few months later fueling up at a gas station,truck was all converted,said it was like a "new truck" with the 7.3 in it..and he was glad he did the swap..said it wasn't as difficult as he thought too..
I only got to peek under the hook for a minute,couldn't see what he did for motor mounts,he was in a hurry to leave..