Using these Billetworkz engine bay caps is easy. Just remove the old caps from your 2008 - 2014 Subaru WRX or STI and replace them with these new ones. They're direct replacements, so there's no need for any special tools or complicated installation. When it comes to maintenance, these caps are built to last. However, it's a good idea to clean them regularly with a mild cleaner to keep them looking their best. Avoid using harsh chemicals or abrasive materials as they could damage the anodized or powder - coated finish. Also, make sure to check the caps periodically to ensure they're still tightly in place. If you notice any signs of wear or damage, it might be time to replace them.