ST 70 power transformer

Happy Friday all, this is my first post here on the forum,( I'm also a tube equipment newbie). I have been working on a ST70 and I'm going thru the wiring looking for cold solder joints or???
I'm looking at the power transformer and the colors of the wires have faded to the point that red looks white, brown looks white ect. Is there any way to determine these colors? Could I remove the trans ,open the case to see if there's any color in there? Obviously the amp worked at some point in it's life; although I don't know it's history. Any advise is appreciated Thanks Gary

If it's original (not modified/messed with) you could download the manual/wiring diagram. I think it's in the stickies area of the basket on this forum. Look at what the trans. wires connect to and maybe label the wires.

I'm just guessing. I built the VTA ST120 kit from new.

Thanks for that, I already have the build instructs and manuals

same advice, look at where the leads are connected and then you'll know what's what