Improved signal path wiring

[Infinitely Baffled]

Hello, all. Does any knowledgeable person out there have a view on this dilemma:

I have a very nice old Croft pre-amp that I'm very fond of. As you may be aware, Croft equipment, being all hard-wired, is very suitable for tinkering and upgrades, and I have a couple of mods in mind for mine. One of them involves replacing the signal path wiring with pure silver wire. My question is this: obviously each "positive" signal path wire has its associated return path or earth wire (for example the wires which run from the earth tags on the chassis-mounted RCA input and output sockets to the star-earth point). In order to achieve the full benefit of this upgrade, do I need also to silver-wire those too?

By the way, have you seen the quality of the workmanship inside Glenn Croft's amps? - Absolutely stunning! Thanks, and cheers. Infinitely Baffled.