Yes, that should be good enough.
Back up scripts/reports etc..
Clean uninstall LR v11.0
Reboot the machine
Install v11.50 <<<You don't have to worry about pre-req as these are bundled with LR and missing pre-req will be installed by the installer>>
Reboot machine
Note down the Host-id on the controller machine and request for the licenses.
In addition, if you have LoadGenerator of v11.0, you can uninstall the same and install LoadGenerator provided with v11.50
Also, make it as best practice to install the latest patches for V11.50.