Call Cresson ridge, +1 (814) 886-4164, they are local to me. They will know
What a mess
For the jake tune up kit, you will need Cat pn#143-6479. On the 3406b and c, injectors are called nozzles. The nozzles stock replacement are Cat...
I have never heard of a steel one, I always use junkyard/good used parts when I need to replace the frame horns in our shop. Sorry not much help
If I'm not mistaken, they use sliding contacts with one(or two) springs sliding over copper/gold coated contacts on the underside of the steering...