How do i go about fitting DCC to the Duchess Of Sutherland from the "R1065 Northern Belle Electric Train Set"

[Mr. Morris]

Hello All!

so i recently bought the set depicted in the title (still unsure when it was made, will put a seperate post out to find this later) and as i was poking about inside it i found that one side of the pickups uses the chassis to conduct electricity to the motor, now i have an idea on how to DCC it but i thought i'd ask you lovely people in the DCC section how you'd go about it as ive not seen power go through the main chassis since the "Railways" was dropped from the hornby name.

so for context as to which duchess i have, its one of the ones with the speedo attatched to the back wheels with the tender having an airfix railway system pre-NEM pocket, similar to what's in the dapol kits that are ex-airfix for the wagons and some hornby rolling stock pieces still using it like the ruston match truck, and its locodrive, i know for a lot of you you don't need this clarification but theres always one that will think i'm on about the tender drive one or earlier tri-ang ones

heres a link to some images of the chassis, i would take soem myself but i don't want to take it apart too many times, delicate speedo and all that: https://www.worthpoint.com/worthopedia/hornby-china-6-duchess-class-complete-538508915

any insight into this would be greatly appreciated :)

[Going Spare]

I have been unable to open your link but looking at Service Sheet 223 covering Duchess locos of that period, R1065 not being specifically mentioned, there appear to be two electrical feeds to the motor terminals from the loco (one direct from a pick-up and the other via the chassis block) and two from the tender via the drawbar. If these are disconnected from the motor and the decoder inserted as per convention, all should be well from what I can see.