I monitor the customer service lines at Silber from time to time. I'm also incredibly neurotic.
The Silber kit and the Sidekick kit are both designed to be as user friendly as possible (yes, I gave a compliment to the competition!). Point is, you aren't supposed to need a lot to make it work. Antistab, torque arm limiters, etc etc are nice, but really if your boost levels are reasonable you will likely not need these.
The **most important thing** is your sled is in proper working order prior to putting the kit on. If you have anything going on, dirty clutches, worn motor mounts, old exhaust donuts, TPS out of spec, dirty exhaust valves etc it'll be extra bad with a turbo! Make sure this is spot on first!!!
As far as what to carry or what to add, here is my $0.02.
1) A lot of this depends on boost levels. I can tell you first hand things get worn a lot less at 5psi (at 8000 feet) than 7 or 10 psi. You may want to consider different drivers/antistab at 10 psi. You do not need this at 5psi (in the mountains)
2) Carry extra exhaust springs. One pops off and it can prematurely end a day - especially if you can't find it and reattach it! (edit: I do not suggest you ride with a spring jingling around under your hood! Still a good idea to carry them as they can stretch and wear out - or you drop one after you find one in the snow. Etc etc.)
3) Throw some high temp silicone (copper) in your trailer as well as a spare donut. I always suggest people silicone these. It can be messy but it can prolong donut light significantly.
4) Clutching. Always have a spare spring with you in the trailer. I also suggest the glide washers on the primary. Really helps with keeping the spring fresh as it prevents bind.
5) I'm yet to blow a QD belt. I don't want to tell you "don't worry about it" but yeah, if you are keeping up with your service intervals "don't worry about it".
6) Watch for fuel pump issues. Polaris actually suggests you change them at 1000 miles. I don't really think this is necessary but I have seen many fuel pumps and injectors go bad. Just something to keep in mind.
7) Relays. This is normal for NA or Turbo.
8) EGT sensor. This is the only other thing I've seen go bad commonly. There is a reason the 18s went to a new one. (if you have an 18 don't sweat this one).
9) Some will say venting, blow hole, etc etc - Personally I run a slightly steeper helix than most which seems to cure most of my belt issues (was getting about 500/belt). My $0.02 is you shouldn't need to do this.
10) Additional intake vents. Cheap. Nice for the deep days.