Well I answered my own question but I thought I would post for other newbies like myself.
While I was not able to find a data sheet for this particular thermistor (E3D Thermistor Cartridge) I was able to find the correct setting on the RepRapFirmware Configuration site.
In the Config.g file...
; Heaters
M305 P0 T100000 B4138 C0 R4700 ; Set thermistor + ADC parameters for heater 0
M143 H0 S120 ; Set temperature limit for heater 0 to 120C
;M305 P1 T100000 B4138 C0 R4700 ; Set thermistor + ADC parameters for heater 1 ;Original
M305 P1 T100000 B4725 C7.06e-8 R4700 ; Set thermistor + ADC parameters for heater 1 ; modified JCD
M143 H1 S280 ; Set temperature limit for heater 1 to 280C
I made these changes and now the hot end temperatures measure within a few degrees of the calibrated Thermistor.
Hope this helps the next guy!