Eric - I coincidentally need throttle cable routing for an 1872. All 82 series CCC with Mag 18 or 20 should have been routed the same way from the factory. Joe, You've just seen too many cobbled tractors!
My need is because my 1872 received a replacement Mag 18 which is probably from a JD. The cable bracket for this spec doesn't use the bell-crank lever so my cable had to make a hard bend to attach, and hence it broke eventually.
dag's pics individually show the end of the cable runs, but I need the path for the throttle from the dash to the carb. dag has promised me he will come up with a few!
I spent part of the day sourcing the pieces I'm missing... the bell-crank lever, correct governor spring, the throttle stop for the bellcrank lever and the actual cable bracket. I'm making this one right, but it's not cheap! Throttle control with cable, cable bracket and stop from Messick's. Bellcrank lever is NLA, found a used on eBay. Spring is NLA, found NOS at a dealer in Maine (Messick's found it for me, God Bless them!).
So, dag, or whoever has, show a good throttle cable routing from the dash to carb. Maybe also get the choke cable routing while your at it. Just put in separate posts if you could. And bring me a beer while I'm waiting!