In this case youre unlikely to do damage by getting them wrong, so I'd
try them at random, with one important caveat. Check each wire for
conduction to earth first: if one connects to the case or plug earth
pin then DONT try them at random.

Theres always some risk you could do damage, but not likely. Do at own
risk if u choose. If you dont want to take on any risk, dont do
anything. For legal reasons I recommend you never do anything. Ever.
Especially not this. Don't do it. Dont even think about it, back away
now.

NT