I'm trying to find instructions on how to change the interconnect and spring, on the FID of a 7890B GC. I'm concerned the spring (and maybe the interconnect itself) has been damaged when a user pushed the spring & interconnect back towards the electrometer). Suffice to say, the interconnect no longer contacts the collector assembly, so it isn't working. Any advice/links to instructions on how to replace either the spring only, or both the interconnect and spring would be extremely helpful. I couldn't see how to take it apart, and didn't want to go poking around with it until I know what to do.