The regulator is usually beside the battery. It'll have coolant hosing as well as LP hosing attached to it. I would recommend you replace this with a new one from the dealer as they are precise metering devices which will be difficult for you to rebuild aa you have no experience with these. Be ready- these are expensive.

Also- make sure your LP supplier is selling you grade HD-5 propane as these regulators are sensitive to contaminants & tar buildup.