I know that CVs can be used to set up control of loco lighting under DCC. My concern is that, when going from DCC-ready to DCC, whether its necessary to alter the original lighting circuitry to either protect/replace the original filament bulbs, because of the possible increase in the supply voltage to them.

I plan to fit DCC/Sound to my J Class loco (Ref. # 82105). It appears to be DCC ready, with an 8-pin decoder socket (currently occupied by a blanking plug)on the circuit board in the tender, the floor of which is perforated to accept a speaker. Do I need to make any modifications to the existing lighting circuitry/components to ensure OK function of the lamps on the front of the .oco and rear of the tender, when running DCC?