Before she passed away I used to get my mother in law into the front passenger seat of our car. It was extremely awkward as she had a stoke and only had use of one arm and very limited strength in one leg, the other arm and leg could not be moved at all and really just got in the way. I found I would stand in the door area, pull her up out of the chair, swivel myself and then put her bum on the seat, then twist her in, then get her to use her good arm on the door frame to help gt her comfortable. It was very hard and I was reasonably strong, most of my wife's siblings would hire a disabled taxi and just wheel her into the back.
That was a standard sedan, obviously in a Morgan you would have the roof off but I know of many MGB owners who have had their windscreen broke by a passenger pulling on it and I expect it would be possible to break a Morgan windscreen as well.
I did think about trying to rig something up in the garage but that would only help get her in and out at home, not at the shops, doctors, restaurant etc. At that time you could buy slings that you have them sitting on in the wheel chair that hinge off the car but my car (Subaru) was not available at that time. This is not what I wanted but similar -
https://www.mobilityengineering.com.au/media/uploads/docs/Kivi_Person_Lift_Brochure.pdf however I feel it might not be a good choice on a Morgan as it could damage the door hinges.
So if you just want to take him for rides in the Morgan on nice days and not take him out of the car except at home you could consider something that hangs from the roof of the garage he can hang onto to help support his weight while you get him in, or even a sling he sits in that you can hang from the roof and raise and lower him.
