Essentially out of economy (or cheapness if you prefer!) a friend of mine and I fabricated a wooden lens board that fits perfectly inside the area bounded by the protruding metal lip on the front standard. Since the board is slightly undersized and would not reach the locks, I used some small cardboard shims. The second generation board will have what I call an "overboard" to cover the face and engage the locks. I see no reason why it shouldn't work. I used the board last night with some 3000 speed Polaroid and could detect no light leakage; worked great.

RA

Image:
http://flickr.com/photos/rafriedman/2195062876/

Nice Philly shots, RA! Love that city. BTW, the eagles on the Market St. bridge there by 30th St. Station came from old Penn Station in NYC.