Frank, I don’t have a pic but after the bottom and side where together, I glued the IP to the brace and while the joint was still a tiny bit soft, glued the whole thing in place and pushed the braces down ‘til the touched the bottom and the IP was still more or less straight up. Then I put into one side of the fuselage just to make sure everything was lined up right. If the angled supports don’t quite touch the floor it no biggie. They disappear under the seat anyway.
Here is what I did with the “stupid joint” Filled it and sanded it flat. Then round the edge of some thick plastic card and glued some 400 wet/dry to it. Roll it first so when you fold it over it doesn’t crack. Using some Dymo tape as a guide I sanded the grooves. These were softened with a small tube of rolled 400 grit following the groove The pic with the grooves is before they were softened a little.