Hi Eddie
In order to support that card you first will need to install an Enhanced FlexWAN module.
Although the Enhanced FlexWAN module supports online insertion and removal (OIR), individual port adapters do not. To replace port adapters, you must first remove the or Enhanced FlexWAN module from the chassis, and then install or replace the port adapters as required.
Anyway, there is no need to reboot the 6500
Hope this helps