Water and a toothbrush will take the fouling right off. It is particulate. It isn't bonded to the metal. I run it under cold water from my well faucet. Then blow it dry with that canned keyboard cleaning air or my air compressor. Spray it with Barricade. Then start on the barrel. When I reassemble the rifle I grease the contact points with grease on a toothpick.
The water and toothbrush will take care of the particulate fouling. Whether the water is supplied from a running tap or scrubbed and rinsed in a bucket, both methods are fine. The drying of the lock is important. Use of compressed air to blow the water away will blow water from most of the nooks and crannies in the lock and speed up the drying. The Pedersoli lock isn't that much different from anyone else's lock. After the lock has been dried be sure to lubricate the lock with a rust inhibiting lubricant and apply a little bit of grease on the parts that slide on each other. Such as the toe of the frizzen the toe of mainspring, the sear spring the nose of the sear and the touching areas of the trigger lever and the sear.
