Can't help being curious - why do you want to use the mini-tuttles? These were pretty popular before 2011 but then - all of a sudden - all kitesurfing boards manufacturers dumped it in favor of FCS or Futures. Nowadays it's a mission impossible to find any spare/replacement fins! Recently I've got my hands on an awesome brand new surfboard, but it's a 2010 with mini-tutles and let me tell you - I was spitting
while trying to find a set of spare fins for traveling as the last thing I want is to be stuck in a middle of nowhere with a broken fin. At the end it was easier to get a set of mini-tuttle==>FCS adapters and some FCS fins (with a huge selection to choose from), especially after TFC quoted me over 175$ for a set. There are still some closeouts out there, but as far as I'm concerned mini-tuttle is a dead end.