XS850 Ignition question

I just received a basket case XS850. It is 80% complete but I have a
few problems. 1. I would like to know which coil goes to which
cylinder (they were not installed when I recieved the bike). 2. One
of the coils does not fire and I cannot locate the problem. Does any
one have an idea on what I should try to pinpoint the problem?

 

Half a gallon of petrol and a match?

 

<snip> I would like to know which coil goes to which cylinder <snip>
My Haynes is missing this detail (obviously), but checking my XS750
trip. The coils are lower left, higher centre and lower right and are
connected to the plugs in the same order. i.e. left to left,etc.
I hope you're only looking for the connections of the plug side of the
coil.

Angelo - 1979 XS750 and still smoking