I found a couple of unused bi matilic strips. At the contact end the nichrome wire is just wrapped around the strip three to four times. There is no mechanical connection and there is no solder. I was able to take tweeters and lift the end of the nichrome wire. It is quite stiff.
Your comments on grounding the truck was interesting. On several 2227 tenders I have found a phos bronze strip clamped under the lamp bracket support against the frame. It goes right across the top of the truck stud putting a fair amount of force against it. I assume it is there to improve grounding. It is on some tenders and not on others. I do not know if it is a Lionel running change or a service station retrofit. The design of the phos bronze strip is consistent so I assume it is a factory made part. But I have never seen it in a parts list and have no idea what the part number is.
