any tips on cleaning out the cowl?

goggles on and an air hose or drive with fresh air doors open at 80 or faster

Last summer I was cruising down a long road out in the middle of nowhere and decided to open up the throttle and see what she'd do... at about 75 mph there was an explosion of pine needles and old leaves that blew out from under the dash from those doors. Hasn't happened since so I suppose this is a viable way to clean the sucker out.