Unfortunately there are not a lot of good options from Yamaha directly or through aftermarket for what your seeking. Most of us buy stuff that is for something else and then modify it to work or just fabricate our own recipe to suit our needs. It really sucks for the Yamaha consumer.
AKHUNTER did a great job for himself. His rig is awesome. You can also search some of the early Gen1 threads for ideas. There is a lot of good stuff buried in there on this forum. Type a search in for chainsaw mount. There are a few threads on that as well.
On my Gen1 I built a headache rack to hang backpacks on or quarters of meat so they aren’t laying in the hot bed. It was very handy. It also had an extra storage rack that hooked into it and all quickly attaches via turnbuckles. No bolting. Rock solid.
In this pic you can see I used to just put my gun in a soft case behind the top of the seats. Worked great with a headache or window behind to hold it.
You can also check out my newly designed hunting camping system for my Rmax2 in BUDROS RACK BUILD.
I’ll pic it up from getting coated tomorrow and later this week add pics of it with gas jugs, axe, shovel, gun carrier etc mounted and finished up.
You should be able to get some ideas for your personal situation by browsing the forum and typing key words in a search. I love my system using turnbuckles because I can add or subtract my cargo options really fast!