I don't think I understand; are
you doing this work, or are you having a tech do it? Are you just sourcing parts for a qualified tech?
When you refer to replacing the power cord do you mean grounding the chassis?
If you are in fact having the work done by a qualified tech (a good idea IMO), I'd suggest discussing the new components with
them before you drop the cash, rather than going by opinions on a website.
A lot has changed in the last 40 years...