I also have a tarpon 140 and i use the free dnr sticker. But since there is not a clear enough spot ,I simply cut the measurments i need out of it and apply them at the correct space on my kayak. For example if i need a 15'' measurment, I cut the #1 and #15 out of the sticker and stick the #1 on then measure 15" then stick the 15 on. I have gotten the entire sticker on the left side of my 140 next to my leg.

Somebody mentioned using the paddle shaft for the DNR sticker. Here's how it looks on mine.

I got one of the DNR stickers and I cut just the ruler part of the sticker out and placed it along the side of my Tarpon 140. It works great.

I put mine on my paddle and cut it where they separate. I also put a couple of winds of electrical tape on the ends to keep it from getting sarted peeling off. It's scratched up, used, and abused but still stuck like glue!

I use the scratch method for making permanent marks in the kayak instead I went a step further. I used a small soldering iron with a rope cutting tip to make smooth indentations. If your good you can also cut in the numerals.

I take the DNR sticker and cut out only the ruler (regs change w/ time anyway) and stick it to the rail of my yak near the seat. Works perfect for me. Supposedly these stickers shrink so you need to be careful if you are near the limits. If its w/in an inch of a limit I will throw back anyway so no big deal for me.

I put the sticker on the bottom of my foot well. The paddle shaft and on the gunwale of the yak are tough. .the paddle is so narrow it's hard to get a good reding and the gunwale... well I have seen fish escape wihtout measurement... when I slap 'em in the foot well they can flop all they want and ain;t gonna get away before I photo/measure them. I also have a floating pvc board I can put in my lap for the smaller ones ( thanks YOTF ) I also heard the saem deal about the stickers shrinking so I do have marks on the true measuerments... plus the stickers are free so if it shrinks I'll just get another one...

I use the 321.com ruler. big and easy to read, works great for CPR tournaments

I just got a tattoo

I cut out the rule, mounted it on my paddle, then cut out the regs square and the individ TL stickers and stuck them to the top of my cooler. I'd be careful about a tattoo - the rules and regs change so much, you'll have to be constantly "X"ing through the old ones and adding a new one...