I have instructed R/C airplanes for 13 years and love float flying. I highly recommend you seek the help of a qualified R/C float flier. Float flying can be a little tougher for someone new to float flying but who has lots of experience from the ground. If your plane is the least bit out of trim the floats can amplify your problems on the water and once in the air.
I am thinking of not only the plane's safety but yours and anybody who may be near you.
Whatever you decide to do - I hope you are successful. Keep us informed.