This is my solution (currently). The mount will accept a 60mm fan which can easily be removed by sliding it off the bracket that attaches to the Aero heatsink in place of the 40mm fan. There is a catch on the mount that is intended to be placed, so the 60mm fan will not slide off due to gravity (it could go on wrong, but should be obvious which way is correct). When the 60mm fan with it's mount are removed, the bracket will allow me to access the screw that was placed under the 40mm fan, and will not require removal of the self tapping screws that mount the bracket.
It's printing now, and I already see some areas for improvement, but hopefully it will help.
Note - the models of the 60mm fan and Titan Aero are not mine, they are from the following sources:
E3D Titan Aero + V6 + Volcano + EZABL Mount V2 | CR-10 | CR-10S
by MP23Racing
https://www.thingiverse.com/thing:2721575
OpenSCAD 60mm x 25mm fan model
by MiseryBot
https://www.thingiverse.com/thing:8063