The easy way requires no adapter. The sink is a little bigger than a 60mm fan anyway. You just put a 80mm fan on and stretch the spring clips out to fit the bigger fan. The little bit of the 80mm fan that overhangs the FOP sink is mostly the outer case anyway. The beauty is, nothing to make or buy. I have a Sunon 80mm high output fan in enroute right now to try out. It's rated 42.5 cfm and 36.5 db compared to the Delta 60mm fan rated at 38 cfm and 46.5 db. Thanks, I'll take the 80mm HO fan that pushes 4.5 cfm more air and is 10 db quieter, please! Note: the regular, run of the mill, average, typical Sunon 80mm fan is rated at 36 cfm and 32.5 db (like I have in the front of my case).