Blocking for fin boxes, tail and nose laminates

Much progress was made from when I started the day before Thanksgiving to mid-December, mostly at night & a couple of hours each day on weekends. Ribs, spar, bottom deck and rails were assembled and glued.
 The next step, blocking out for fin boxes, the tail and nose pieces, stopped me for weeks because it meant finalizing board length and dimensions, including where fins boxes would be placed. Many, many hours searching Swaylock's, Googling for fin placement, looking at board dimensions from known shapers, and calculating where to cut off existing tail and nose decking & spar as that would affect tail and nose dimensions @ 12". It's nerdy, but I created a spreadsheet with a dozen similar boards and their dimensions - there's no surf shop nearby nor anyone in Glen Ellyn, IL who shapes and could guide me so I got analytical with info off the internet.

Measurement above top of spar	Length	Nose	Width	Tail	Thickness	Notes
	7'10	16	21 3/4	13 1/2	2   5/8
0	7'8	16	21 3/4	14 1/2	2   5/8
0	7'6	16	21 3/4	15 1/4	2   5/8
1"	7'10	15 1/2	21 3/4	14 1/8	2   5/8	Given where my rails are already set, these dimensions seem to be a good target.
1"	7'9"	15.5 / 15.5	21.75 / 21.5	14 2/3 / 14.25	2   5/8
1"	7'8	15 1/2	21 3/4	15 1/4	2   5/8	Close to an Enzo Egg
2"	8'0'	15	21 3/4	13 5/8	2   5/8
2"	7'10	15	21 3/4	14 5/8	2   5/8	Could be made into a Harbour Drifter Shape - 7'10", 14.25 nose, 21 3/8 mid, 14" tail with a narrow squash of 4-5"
2"	7'8	15	21 3/4	15 5/8	2   5/8
2"	7'6	15	21 3/4	16 1/2	2   5/8
Comps
Murphy egg	7'10	15 1/2	21 1/2	14 1/2	2   3/4	Rounded slight pin
Murphy Enzo Egg	7'10	15 1/2	21 1/2	14 1/4	2   3/4	Broad pin with distinct 'point'
Murphy Retro Egg	7'10	15	21 3/4	14 1/2	2   3/4	Pin, less broad than enzo
Harbour Drifter	7'8"	14 1/4	21 1/4	14	3	Narrow squash ~4-5"
Harbour Drifter	7'10"	14 1/4	21 3/8	14	3   1/16	Narrow squash ~4-5"
Harbor Sph Revolver	7'8"	16 3/4	22 1/8	15 1/4	2   7/8	rounded a little pin
Harbor Sph Revolver	7'10"	16 3/4	22 1/4	15 1/2	2  15/16	rounded a little pin
Bear Versatile	7'6"	14	21	14	3"	Squash 6-8"
Bear Midrange	8	14 1/4	21 1/2	14 1/4	3	rounded pintail
Haut	7'6"	15 3/4	21 1/4	14 1/2	2  22/25	squash - ~6"
August - Corky Carroll	7'6"	16 3/4	20 7/8	14 1/2	2   1/2	broad rounded pin
Hawaiian Pro Dsns	7'6"	16 1/8	21 3/8	14 3/4	2  14/25	Rounded Pin

 
After much figuring, I asked Chad Gross who created the plans as well as Dennis Murphy to check my plan to see if they made sense. Both were very helpful with suggested locations for fins given  dimensions and also gave advice on blocking materials, sealing the interior, etc.

These pics show what I did to block out the tail for the tail block and fins.  I took a Sharpie and wrote all the dimensions down so it'd be documented. I also took a big piece of paper and traced where everything was - I'm paranoid about doing all this work and then routing for fin boxes and getting hollow board. The blocking is balsa from the local Hobby Lobby. When glued in the balsa  stuck up above the ribs so it was shaved down with the 6" planer and some hand sanding to be level with the ribs and spar. Make sure you plane with the grain as balsa is soft and will rip and tear easily.
The top of the "T" (bottom of this pic) is where I'll glue the tail block. It will be 3" long so the top of the "T" is where the tail block will be glued and I'll shape the tail to be 3" back from the glue edge. The next step is to cut off everything to the right of that tail block.

I also glued scrap balsa blocks to the ribs so there'd be more surface area to glue the top deck.