The MRX5 can be used with the Hudy On-Road StarBox it works for me
i cant take a picture right now but ill try to explain.
No cutting what so ever, using parts that came with Hudy starbox
Get the manual that came with your Starbox.
On the front page look for Face Plate #104412 remove it (4 screws) from the starter box.
Assemble Y Bracket #104413 as on page (3) three Alternative C in the backward direction
DONT USE LONG PLASTIC LOCKNUT
#2 at the bottom of the picture.
Take Y Bracket #104413 mount it like on page (3) three Alternative A (Xray NT1)
instead of going up with the screw,
go down thought the Y Bracket #104413 and lock it in place
with one of the plastic lock nuts from Alternative B there (2) two at the bottom of the picture.
Reason for using this part is so you can get the face plate on.
The Alternative C #1 bracket post on my starter-box are directly behind the front arms.
The rear bracket post are under the rear arms BUT they squeeze the chassis keeping it centred.
Reassemble and your good to go.