Check out cboats.net as there are a lot of conversions that have been posted, take your time and you will find some really good ones.
Also I have Super Rad 180 which is kind of similar and it paddles great, there have been a few people that have converted projects very successfully and they look great. There is also a Fluid Nemesis that was just converted.
Also I have a blog that might help, deepsouthc1.blogspot.com/
It shows how I did my seat, although I have taken the adjustable backband out and put a full minicell seat back in.
cheers and good luck
Hippostan