Radio install in new RTV 900

My plan is to mount a radio package from Northern tool...the one that has two speakers and the radio mounted in a an OK looking console that goes overhead...will pull a hot off battery with a fuse block and hook it up to the always hot but put a switch in so the clock wont drain battery if the machine sits a few months (shut the switch off). Will use the hot to run the radio and radio switch will turn power on and off...that way it wont run down battery with key in acc position if I want to listen out in the field with the motor off... and no need to find a switched wire to run to radio. Just want know if that sounds right...or is there a magic wiring harness already installed that is easier to use? hard to figure out wiring on a brand new machine. What am I missing? Thanks

Radio install in new RTV 900