i can tell you the boost bottle actually helps with sleds; they don't have a x-over tube stock, and it's easy to smoke a belt on the trails, but it helps keep that from happening. i have heard of indexing years back, but it's not one of those all-popular things. i don't know if facing the plugs tward the intakes is right, but on larger bores and four strokes, there is a higher velocity across the plug which is evident on a plug that has been left in long enough to see the wear. it seems like shiming the plug to get the proper index would be a littl unreliable, and could cause your plug to come loose, but i have been modifying the combustion chambers on different engines to combat which has shown increase in power and efficiency, but that is a story for another day.
long story short, i wouuldn't recomend it, but you would probably be better off looking into side gapping instead. :thumbsup: