what you need for an MSeries Arctic Cat setup:
-1 side of a 2 set atv gun rack
-1 complete old snowboard ratchet strap both male and female parts
-1 plastic extender piece (i used part of an older board strap
Step 1: back when GIJOES was around (so bummed they closed) I went there and bought a set of ATV gun racks for $40, choosing the right set is crucial as you do not want ones with any mechanical or moving parts. just a nice solid base and a Y grip that does not rotate unless you pull the rack off completely. make sure its one with the 4 hole base as the ones with 2 holes will slide and rotate and will result in a FAIL.
this is the exact Rack i used http://www.tacticalandhuntinggear.ne..._ATV_Racks.cfm
Step2: take one of your rack setups and bolt it down to your back bumper, make sure the Y is at an angle so when you slide the board in its a snug fit.
Step3: slide your board strap through the tunnel rack and fold the end so you can use a bolt and nuts to attach it to the tunnel rack.
Step4: drill a hole in the side of your tunnel to bolt the male strap part to it so you can connect it while board is in it to your board strap and ratchet it down.
done.. it took me about 20 minutes to set this up myself and the majority of that time was just making sure i had my angles right and enough room for the board to fit in there.. last season i found out we could actually put 2 boards in the rack.. awesome!
1700 miles so far with out failure.
here is the completed setup without board.
different angle with out the board straps linked up.. this one should help