The air filter housing lid is notorious for not sealing well. You would need to eliminate the entire air filter housing and connect directly to the intake tube. We built some above bed pre-filter kits for both the intake and CVT side. You maintain the stock filter, just allows to get the intakes in a cleaner air path and pre-filters. Worked out well, but we discontinued due to limited sales. Might be able to put a kit together, give us a shout and we can see if we can help you.
Regards,

 

you may have seen an s&b particle separator or a KWT filter.

 

I run pre-filters on mine for the reasons you stated.

 

Here is what I did!
I took the stock air filter out of the engine box and mounted it vertically behind the drivers seat.
All the intake parts are gone. Intake air goes in via ABS (sewer pipe). Elbow thru the bed then straight shot into the throttle body. Added a rain cap to the top of filter box. Granted, the filter box doesn't seal well but it doesn't matter.
Those 2" rubber couplings slip right on to the throttle body and filter outlet and make a good tight fit.
Intake Air Temp at the throttle body is now down 20-30 degrees F. cooler.
I'd add pics but my RZR is put away for the winter.
Fred

 

Thanks to all for your responses. I've got some thinking to do on this.