You can coat the inside of the cowl with this or cavity wax the sprayhead sprays in every direction on the end of a long plastic tube that you can bend around
Go through the heat vents and any hole you can get the nozzle in and make sure you have eye protection and a disposable paint suit will help.
It sprays real fast and makes a mess on everything and doesn't come off real easy. Don't ask me how I know. lol
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