upgrade from snow lion server to el capitan
I have a mid 2010 mini server with Intel Core 2 duo hard drives. On one HD I have Lion (non-server). I no longer use the server. It is basically 500 gb wasted. I want to delete the server software and install El Capitan. This is so I can partition the (hopefully) former server disk drive and install bootcamp so I can run windows 8.1. Snow leopard server does not have bootcamp, and besides, I am uncomfortable with having windows on the same drive as the server. I had the Lion OS partitioned to do this, and stoopidly updated windows, which killed that boot. So I restored the Lion HD to one partition running only Lion. My question is: As part of the El Capitan install, will I be able to erase the (server) drive for a clean install?
Thanks.
Mac mini Server (Mid 2010), Mac OS X (10.6.8)