He didn't say no. Ouch.
The SLC series of processors are not hot-swapable.
It is likely that you have a fairly expensive paperweight in that rack.
However, it may be that the SLC has only had it's memory wiped (the hard way).
Have you tried connecting to it through the serial port (and perhaps doing an Autoconfig in RSLinx to find the default baud rate)?
If the memory is wiped, the IP address will be gone, and you won't be able to communicate via ethernet (for the time being)