start off by its a 93 DA no AC, and the vents inside is vilthy dusty, so i though maybe having it on full blast and letting it all blow out will fix it, did it, but theres soo much leaves and dusts in it i guess even after they came out there we're more on the bottom ??? how can i clean this, i cant find a way to take the grilles off without scratching or damaging anything, is there a filter for this eventhough there no AC ?