The do it yourself plans for the AI are free to download on my website. For the TI, just cut 4 inches off the narrow end, will get it close to my TI kit fit. Also, my wife Dee does sell just the sewn Sprayskirt with twine in it to pull your own lines, for about 1/3rd less than the full kit.
The value of the Kit is it takes less than 10 minutes to do the basic TI kit install verses hours customizing for the non-kit, and the fit is exact (after many years of tweaks). I only do kit installs myself now, as I can't beat the fit the kit gives.
- - - - - Hobie Island Sailing since 2006 - - - - - 2011 & 2015 Hobie AIs and a 2012 TI