The Hub City PTO Reverser can fit on a 184 with the correct mounting bracket.
I have top two of the reversers shown in the pamphlet and neither one has the fits the 184 without drilling new holes.
Here is a pamphlet that shows the different model numbers used on the cub lineup (and other tractor models) Notice the 184 is not mentioned. The top one definitely doesn't fit the 184. The bottom 3 do reverse the direction, but doesn't slow down the RPM's. I think the proper one is the second.
This is the picture I have of somebody's tractor. (with a 3-point hitch) I'm pretty sure at least one hole was drilled in the PTO plate. I can only get one hole to line up with a factory mounting hole.
Here is a rear view of the mounting.
This is the Hub City Model # that is shown.