First there is a hole.... or two and then the fan is ground into the radiator, good and tight.
Remove fan, cry, look at fan, do a little more crying. Pull radiator, find: tools, solder, and Advil. Go find auto parts store still open on July 4th. Find new fan. Start picking, pulling, soldering, praying and a little swearing. Fill radiator with water, hold breath, watch, wait, watch some more. Put radiator back on car, attach fan, wire fan, test, pray, clap, get more Advil.