First new build with 2 harddrives -- how do I install OS?

The easiest way is to just install windows with only the SSD connected, then after you get it up and running shutdown, connect the HDD and then set up the HDD using the windows disk manager.

Nope just select the SSD as the one for the OS and it will be labeled as C drive by windows. It will then label the HDD as another letter as well as the disk drive.

That makes sense. But would it be necessary, as long as it clearly asks me which drive I want the OS to be installed on? Is there another reason why it would be bad to have the two drives conencted when windows was installing?

Thanks for your help!

I suggested doing it that way because it is easier not because it's the only way or even the best way. You can definitely install windows with both drives connected and just make sure that you select the SSD to install to. I have occasionally had problems doing it that way because sometimes the BIOS wants to use the HDD to boot from instead of the SSD even when the SSD is the only drive that has an operating system on it.

Great, thanks so much for the help!