H&Kettner Switchblade 50 Combo to H&K 412 Cab ohm?

[Shinobi'sZ]

I have a Combo amp and it has 4 speaker outputs on the back, 4, 1x8(2x16), and 16 ohms. I have a H&K 4x12 Cabinet I just picked up, it has two inputs, one for 4ohms (mono) and one for 16ohms (mono).

I have disconected the interal combo speaker (hooked up to 8 ohms) per the H&K manual different speraker outputs can't be used simultaneously.

My question is what output (4, 8 or 16) do I use to the Cab...the cab doesn't have an 8 ohm input..so I'm guessing that I either use the 4ohm or 16 ohm output from the amp into either the 4 or 16 ohm input into the cab?

Thanks