Mona Lisa Paint Thinner can be used to remove over-sprayed paint, such as enamel over lacquer. Using a cotton bud (e.g. cotton swab, Q-Tip, etc) dipped in Mona Lisa Thinner (probably best to not over-saturate), lightly scrub over the overspray, and it will gradually come off of the undercoat.
Mona Lisa is widely used by modelers for weathering due to its ability to leave underlying paint layers alone, no matter the paint type.
Mona Lisa is available at Michael's, Ben Franklin's, Walmart, Amazon.com, Joann Fabrics, Staples, Home Depot, and many other craft and paint supply stores.