It looks like your third frame is off - it shouldn't be so flat across the bottom. Since the chines look ok, you could just add a filler block between the keel and keel notch in the cross frame to make up the difference for a quick fix. This may cause the boat to be rather uncomfortable since the cross frame will most likely hit you right under your knees or calves. Best practice would be to re-make frame #3, but using the filler block would also be acceptable if you ignore the possible comfort issue.

: I AM INSTALLING THE KEEL ON AN OTTER-R (YOST DESIGN) HOWEVER THERE IS A
: SIGNIFICANT GAP OF ABOUT AND INCH AT FRAME 3 AFTER ATTACHING TO FRAME 1
: AND 6. IF I PULL THE KEEL INTO THE FRAME IT HAS A CONCAVE LOOK TO IT IN
: THE CENTER IF I LEAVE IT IN IT'S NATURAL POSITION IT IS CURVED EVENLY FROM
: BOW TO STERN. ANY SUGGESTIONS? THE GAP CAN BE SEEN THOUGH NOT CLEARLY IN
: THE ATTACHED PIC URL.

: THANKS