I have a prewar 3651 remote lumber car that doesn't operate. Upon opening the bottom casing I discovered that the wiring from the trucks to the solenoid is badly cracked and needs to be replaced, and also the plunger and linkage to the platform control arm are missing. It looks like the trucks need to be removed to replace the wiring - is there a trick or special tool to use to remove the clip that holds the truck in place? I'm reluctant to brute-force it with a flat blade screwdriver for fear of badly scratching the paint around the clip. The car isn't that clean to begin with, and I don't want to make it any worse.
Also, it looks like the missing part I need is #3651-14, "Plunger Assembly", which I found on eBay. Is repairing as simple as connecting the new part to the control arm and inserting the plunger into the solenoid? Apologies if that's an obvious question but I've never worked on the solenoids before.
If it matters, the electromagnetic uncouplers do work.