Recomended Mods for a M8 - no far fetched stuff!!

sell the can, and buy the slp y, pipe and can combo; no fuel mods needed.
and skip the supreme tool valves, bikeman makes exhaust valve spacers, for $19.00 gives you great mid range punch. and stop buy your cat dealer for a 42/36 helix. makes your cat into a dragon slayer you'll love it....

I don't remember what the boards look like on the 08 tunnels, but one of my cheapest and favorite mods has been the sno eliminators on my 07 M8.

Since you have a risor and can covered I would grab an slp pipe/y pipe and match that with your jaws can. You will then need a bd box to keep everything runnin safely. After that a good set of snow eliminators (pick your brand), side panel vents to keep everything cool (again pick your favorite brand). Then after that a good intake from timbersled or bdx helps out a ton. Get you clutching dialed in and you will have one mean running sled. After all that you can gut all the insulation on your hood, and side panels and loose some weight there, you can add a boss seat to loose some more pounds. I think those in my mind are a few good things that are fairly cost effective and work really well.

SLP pipe at 6-9K I would run 70G weights with a stiffer primary spring around 320-340 finish rate and that will give you 8000rpm at 9K. Some run 68G weights with lighter spring and have good luck but I prefer the heavier weights and spring as it pulls harder.