Hi...I was just wondering if you could use the most recent types of stud finders for that application. I don't do much with that type of work but I know that my (very new) stud finder uses density to find stud locations, rather than by locating metal nails or something like that. They claim that this method is more accurate, and since buying it I have used it extensively in trim applications with a 0% failure rate (not kidding!). Ok, well it's just an idea/suggestion for finding the studs behind plaster, but again I have no idea if this would work. The sensor I use is a Zircon Studsensor Pro 4.0 ($19.99) and also has "deepscan" capabilities. Jeff