Coil HT Lead Connection

I'm in the process of replacing the ignition coil on my S1 and need
a little help. The coil currently on my car is not correct for a
3.8 series 1. It uses a plug-in HT lead instead of the screw in
variety, so I can't just look at what I have to figure this out.

I have the new coil with the screw in HT lead, the screw in HT nut,
a copper washer with a radius slit, and 21' of HT wire. The nut is
really no more than a sleeve that must hold the copper washer
against the HT contact on the coil. But how do I connect the HT
wire to the copper washer or am I totally missing something? Do I solder the washer to the wire? What is the slit in the copper washer for?

Nick - 64 OTS