fenders are generally the easiest.. you will be plumbing off the hyds port on the top cover? or a front or rear pump? keep those plumbing lines in mind.
some loader frames have the spool on an uprigth frame mount about even or a lil forward of the steering wheel.. either side depending on make.
you could propably fab up an angle iron bracket and attack to the right side of the hood, near the steering wheel. that will put it up and out of the way of the steering arm and not prevent entry/exit.. also won't be in the way of the air cleaner which has a few bits under the left side of the hood in that area.
I'd use large fender washers on the backside of the hood.. or a short strip of flat bar stock or more angle to back up the bolts.. won't take much.
on my naa i mounted to right fender, running lines ove rthe axle trumpet and upthe side to keep them out of the way.. on my 850 they are on the right side of hte steering wheel on the frame of my superior loader.
I think if you try to make a trans bracket.. you will run into problems witht he steering arm..same using running board mounts.
lastly.. both R and L side of the tractor bellhousing has flats and tapped holes. an angle iron bracket could be rigged up to attach there then travel up and then back a bit to make a perch for your valve cluster. .. could make a small stabilizer to the hood with small stock.
i'd got with fender first ( not what you want ).. and then 50/50 on the hood or the bellhousing mounts.
most of my machine already have a frame in the bellhousing mounts meaning hood.. or attaching to what already inthe bellhousing mounts. etc.