thanks a bunch 4est. and solstice…and everyone who contributed answers…i think i’ve finally got it figured out. can’t wait to finally shape it and see what happens. thanks again :)!
Oh yeah incase that was confusing…
find where the blank is 18.5" (1/4" per side working room to template cut from) and then measure forward 1 foot from there. This will give you the starting point for the nose to measure from. Does that make sense?
Then you can measure off from that point to see what your tail rocker situation will look like for different lengths. I’m no rocker expert but using most of that nose rocker for your tail won’t hurt. Look up in this thread and the other 10’1Y thread to get some thoughts on tail rocker amounts. If you use the whole thing you’ll be on the high rocker side, but not out of tollerance.
if you are worried about the nose rocker you can always shape some back in when thinning the nose from the bottom, but I would not worry about specifically adding it. Some will occur just from the thinning process.
Have at it and have fun.
glad you seem to have got a handle on things now…but for future reference, your rocker comparison method is a bit flawed because it gives more of a comparison between the BOTTOM rocker of one with the DECK rocker of the other. try putting them side-by-side, with the more heavily-rockered board in the back, and then take a profiled view from the side. remember, you shape the blank primarily from the BOTTOM…so it’s DECK rocker that you should be looking for.
barefeet,
Give Swaylocks a chance to be as effective a possible in advising you. Provide info as to your surfing experience, where you surf, the type of waves you ride. Post the info, or use the user profile. The guys that have taken an interest in your request have been giving you excellent guidence. The following is my contribution: For your weight (155#) I think you should consider 9’8" X 22", 17"nose, 15 1/2" tail to a 6" square. To put that in perspective, I’m 6’0" 225# and ride an 8’10" X 23" with a 17" nose. This is the widest board I have ever made for myself. Why? Floatation. I don’t believe you need anything near a 23" wide board to float you high and dry, as well as paddle like a rocket. Good luck on your project.
I agree with Bill. If you template out your nose at 18", shaping will bring it down to 17.75 but glassing will bring it back up. 18" is a lot of nose for your weight, heck, 10’0" is a lot of board for your weight. I’m 215 lb and can noseride 9’6"'es if I want to paddle that much 
Just like Soulstice & 4est said - find your nose spot on the ‘tail’ of the blank & run all your other numbers from there. Don’t even stress about the tail rocker - there’s a reason hundreds of shapers have made thousands of noseriders out of that blank, reversed. Just go with it.
One other thing is that you could easily shape your board as around a 9’8"-9’10". Finish shaping completely. Then cut off the last 2" and put on a 1.5" tail block. Smooth it to match your rails but you can easily relax the kick just a little with that. You can also thin the last 6" or so from the deck side instead of the bottom side which will further relax the rocker and you don’t have to worry about heel dents. You can stomp on the front of the fin all you want but hardly anybody stomps on the last 6".
Bill . . .
Took a while but this guy finally hooked you, huh? LOL! Maybe it’s time for you, Jim, and a few others (Morey?) to write an intro level treatise describing basic surfboard/longboard design theory. Bless their little curious, questing, and creative hearts, but these guys need either a lot more waves or one or two good texts.
Barry
Caught me! Guilty as charged.