Years ago, a prominent WCHA'er and I stripped a Penn Yan seagoer trailboat without removing the canvas. Using water wash stripper, we kept the section to be stripped as vertical as possible, applied the stripper, and scrubbed it out. As I recall, we had some liquid refreshment to ward off the fumes. There was minimal bleed through to the canvas. Seagoers had an airplane dope filler so any filler bleeding through would be obvious. It can be done. I believe this to be correct, but with all of the white lead and stripper to which I have been exposed, it could be a fantasy.