Nabokovfan87: I checked and the fitment is fine, including the hinge and trim piece. There's enough leeway that none of the lid is actually "catching" on the rim. But I'll keep that sanding tip in mind since it might save me a future trip to the E.R. 😉
The first picture is sort of a cutaway depiction of the problem area. It only shows the contact between the lid and inner lips of the side rims. In reality, the "seal" extends all along the inner lip of the front rim too.
Well, I went into my "Hmm, I might need these some day" repository and found a bunch of little self-adhesive rubber squares from some old electronics project (second picture). I stuck one to each front corner and one in the middle of the of the lid. So far, so good - they eliminate the "hydraulic seal" and only keep the lid open a crack. But I have no great hope that the adhesive will survive long in a warm, moist environment.
I think my next step might be to fabricate a few clear plastic clips to fit over the frame and between the lid and lip. If I do, I'll be sure to update this thread.
And thanks to all who have responded or will respond.
-CB