Impedence advice needed

What are the recommended impedence settings for
the stock speakers in the following combo's ?
410-sixty five
410HD-one thirty
210-sixty five
210HD-one thirty
I have always thought that the 8 ohm selection was correct, but have gotten confused reading some of the posts in this section.
Appreciate the advice, thanks Jim

apparently the 210 sixty-five should run at 4 ohms. The 8 ohm setting is if you run another 4 ohm extension cabinet as the speaker outputs are wired in series. (or so my speaker repair guy said)hope this helps!