How do you find the wall studs without removing the plywood?

[digimark]

Thanks for the advice. I went camping in the trailer over the weekend and then took the trailer into the dealer, who secured the cabinet for me. I bought some #10, 2 1/2" self-tapping metal screws and washers to use in stabilizing it, but I don't know if they were used. I'll probably
revisit this problem if/when I install a second shelf.

Now I have to pick up some locking door latches so the doors stay closed in transit...