How to identify the RP and SP in 6500 series
When you first login into a C6500 switch you enter directly to the RP. From there, you can connect to the SP with the command remote login switch and your prompt will change to the swith hostname followed by -sp such as: mycisco6500-sp#
If you want to toggle from the SP to the RP you can type the halt combination Crtl+SHIFT+6 and then x key. To return to the SP just press Enter key.
Hope this helps.