How do I install new hard drive in my Mac Pro A1188?

Here’s a helpful information from Apple themselves. So as far as I’ve found, this is a full guide for the Mac Pro; including how to install the hard drive:

https://cdsassets.apple.com/live/6GJYWVAV/user/ma182_mac_pro_user_guide.pdf

That generation of Mac Pro can take any normal Serial ATA hard drive. The easiest way to reinstall Mac OS X will be from the original installation disks, though if you can make a bootable USB installer for a version of macOS up to El Capitan, that will probably work.

Regards.

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