R230 - How to add 5th SSD for dedicated OS??

I have an R230 with a PERC H700 card that I need to set-up as RAID 10 with 4 x 3.5" HDD's.  I also need the OS to be separate from the RAID array - on a single SSD of some type.

It looks like someone suggested replacing the ODD with an SSD here, but a Dell moderator said this wouldn't work, but he may have other options.  This is a Win 2016 server installation.

Does anyone have an idea on how I can do this?  Can I use a PCI to M.2 adapter and boot from this?

Thanks.