Have you considered a pull behind attachment? I recently bought a couple of pieces from a guy north of here, made by a company called Giant Vac.
One is a blower to blow the leaves into the swamp behind his house, and the other is a yard vacumn. It picks up the leaves and stores them in a hopper, till it is loaded (holds a lot!!) and you remove two wing nuts, grab a handle and raise it up. Pull forward and it is unloaded.
My thoughts are it would be easier to buy either a vac or a blower and pull them, then to try and adapt one to your MMM and not be sure if it would work.
I have entertained the thought of plumbing the blower into the mowing deck of my Steiner, to pick up the leaves and then blow them into a trailer, but pulling double trailers in my yard doesn't make since when I have the vac.
Before the vac, I just blew them to one side of the yard where there is a ditch, and let the next rain wash them away.
Depends on your situation
David from jax