I have been looking into this, but hard to get time lately.
Yes I think it's possible, but not quite as straight forward as it immediately looks. This and other gearbox fun was intended to be a summer project, but setting up the workshop is taking it's time.
I do think that merging with the flat flywheel is probably easier if you don't need the dished flywheel. Do you need the heavier flywheel?
The shape of the ring, where it is welded to the ring gear, makes it more difficult. I also don't think that just pressing it on will be safe. It looks better to keep the auto flywheel intact and machine a flywheel to fit in its centre to match the contour. The bolts into the crank can then sandwich the two parts, and the there is no potential for a timing angle error from a machining error, as could happen when modifying a flywheel. I will post what I discover.