Hi dStruct714,

To answer your question, the 'extension' is the type of filter they have designed this particular pre-filter for (click on this link [link=http://www.outerwears.com/products.asp?cat=12436]Standard Genesis/Nemesis/GST Air Filter[/link] it gives details of pre-filter). Just happens to be the correct diameter, just a little too long, but according to the correspondance I have had with Outerwears, they tell me that won't effect its operation.

As for relocating the CEN Air Filter, I had simmilar thoughts as you. But after seeing TRD's relocation option, some time ago, shown here in [link=http://www.rcuniverse.com/forum/m_5999450/tm.htm#]post #19[/link], I have decided I will probably go that way - Thanks for the idea Dogman. Mainly for two reasons;-
1/. Raising the filters existing height / location makes it prone to fouling the handle/roll bar, when lifting the truck & whilst removing the filter for replacement.
2/. TRD's relocation position will place the filter into much cleaner air (longer run time between cleans) & at the same time give the motor & it's head a more undisturbed flow of cooling air. Plus, whilst this whole assembly is kept low its chances of being damaged / ripped off are a lot less - so less risk of your motor getting unfiltered crap into it, to damage it!
Plus according to TRD the extra distance between the filter & carby, has no noticable determental effect to engine performance or output! Win Win!

I will post the results in approx two weeks time, I live in Australia, 5-8 days delivery time + I need some time to test.

Regards, .46NitroAddict [>:]