I want to inspect the hull below the cabin floor of a 1968 RQ, I think I can cut an access to inspect the keel from the back of the cabin to the steps by cutting thru the plywood directly over a supporting 2X4. This will make about an 14 inch wide gap over the keel. Has anyone any experience with this? Am I missing an easier way to verify hull soundness, I want to avoid sandblasting the hull. Also if I gain access I can clean and paint the keel on the inside and prevent any more rusting. For the portion below the elevated part of the cabin, I noticed it is screwed down and can be removed easily. thanks for the feedback TR

I bought my second new Queen, 38', in 1972 and I have been very
satisfied all these years.  I did early on what you proposed to do
now at this late date. Your idea is inexpensive and time well
spent.  Start by removing the carpet and pencil an 8" path over
the centerline of the hull. Use a circlular saw adjusted for the exact
thickness of the plywood and save the plank that is removed.  My
frig sits 10" from my cut and I had to reinforce the floor in
front.  Decide if you want thin aluminum or stainless batttens
(about 2" wide) attached to the top side of the plank and they can be
attached over the cut rug or the rug can be left uncut and moved aside
for access.  Ther other method is to install the battens along the
bottom side of the floor so that the plank rests on top.  Wood
battens, 1/2" x 3", could be used here. The plank can be cut to
convenient lengths for convenience.  Be sure to thru bolt the
battens with countersunk heads and heads up. Don't use screws which
River Queen did when they made accessible hatches in cabins. Mine is
uncut rug over lower aluminum battens. I have been able to maintain a
dry keel.  Good idea to install an emergency bilge pump at this
time for the unforseen.  Don't panic at what you might see inside
the keel. A putty knife and shop vacuum can clean up the mess.  I
eliminated sleepless nights by contracting a welder to weld 6" x 2'
thick mild steel plates to each bottom side of the V for the full
length.  A few years later I did the same to the outside.  I
accept emails.  Good luck and safe boating.  DES