I have a bx2750 blower for my 1870. I also have a front blade. Ideally I would have a rear pto blower and front blade.
Is there any hope of modifying the bx2750 blower to use on the rear 3pt/pto? Right off the bat I noticed that the PTO spline seems smaller on the blower. Is this idea crazy?
It has been done but.....
Far better to sell, trade your front blower and look for a 3 pt one.
There seems to be people looking for front mount units.
Clean it up, a bit of spray paint and you should have no problem selling.
Find a used 3 pt, post some pictures and you will get fast feedback.
The unit needs to have a high quality gearbox. Anything else is off the shelf stuff for repairs, chain, sprockets, pto....
I looked at your unit on the Messick's web site. It has the walk behind snow blower style gear box located between the two auger halves. 3 pt blowers will have a heavier duty gear box
With the fan on the input shaft to the gearbox, if there are direction of rotation issues they will be hard to solve.
There used to be blowers which could easily be altered to work on the front or back. This is an example of one of them.
Dave