Im not that great of a tech but, are you making sure you have the right amp/voltage fuse that you are replacing? check all the wiring to the flipper to make sure it isn't shorting out somewhere (like exposed wire touching metal). Is there anything else on that same circuit? Possibly your flipper coil is gone and you need to replace it. Do you have a DMM (digital multimeter)? Set it on DC and check the voltage going to the 'good' flipper and the one that makes the fuse blow. If they are different, check for a short in the wire (like I said), or there might be some wacky voltage going to the coil that might be traced back to a simple diode or even a PCB board, and when you activate the flipper it blows the fuse.

yeah Richy Rich thats an 11c board in that 'Radical' game, falls under Williams/Bally wpc
any Diagnostic message? Not sure how much knowledge you have on board repair
but if it was my game I'd send all the boards out and get them tested -however not to jump the gun do what jbscar suggest you might find something right away- an easy fix?
http://www.pinrepair.com/wpc/index3.htm#odd