Thank you...
I appreciate all the response on this. Sorry your flange cracked... I think I will have to replace my floor flange, too. It looks as though it was filled with plaster, or something like it, at one time. I don't mean the part the pipe goes in, but the underside of the casting. I was washing the inside of the boat (it's stripped) with a hose, and about a pound of sand came out of the weep holes. Perhaps this "stuff", whatever it is, helps the whole thing corrode. Anyway, thanks for the dimensions... from yours and other responses, anyone missing a table should be able to make one which won't trap them below. Rich.