New guy here with Another 660

I’m new to the Grizzly world. Wasn’t really in the market for one but came across a deal I couldn’t pass up. It needs some TLC but nothing I shouldn’t be able to handle. Not sure of the year but think it’s a 2006.
I would like to do whatever mods there are for this thing. I’ve browsed briefly and saw mention of a couple things to do for overrides of starting and shifting??
Can someone point me in the right direction as to what I should do first and how to do it????
And of course i’ll want to be doing performance upgrades as well so i’m looking for suggestions. I want to keep it fairly quiet so no loud exhaust.
Thanks in advance for all your help and patience :peace: