I also got the aft cabin bunktop taping areas ready, for doing the flange for the starboard bunktop half. I think I will put the port hull half back on the 2x4's, then slide it over to the side so that I can work on that flange from the outside of the hull - it would be very difficult to do it from the inside. But that will be the last thing I do - I don't want to move the port hull half until absolutely necessary, in order to keep everything aligned as possible. Overall, the bulkhead alignments are turning out really nice - I am pleased.
I'll have to squirm through that passageway above to get to the aft cabin, when I tape the aft cabin fwd bulkhead - ought to be a lot of fun. :)
Also got the beam mount flange extensions trimmed. First I made a template that matched the side-profile:
After marking the side profile with the template, I used the jigsaw to cut off the really big chunks. After that, it was full speed ahead with the sander (hallelujah for 40 grit!), grinding all of the edges into shape. I am very pleased with how they turned out -- from some angles, it's hard to tell which half of the flange was the original. Here's the finished mounts: