Triple Boot Two Hard Drives

[Coaleb]

So I want to install Ubuntu 16.04, Windows 10, and Sierra onto 1 SSD and 1 HDD. I have Windows 10 Installed on the ssd and I want that to stay like it is if possible. The Hard drive has 3 partitions right now one for Sierra, 1 for storage, and 1 I'm wanting to use for linux. How would I go about installing Ubuntu on the hard drive without overwriting the clover bootloader? Last time I followed the guide it overwrote the clover bootloader and I had to start from scratch on the Sierra side.

 

[Going Bald]

So I want to install Ubuntu 16.04, Windows 10, and Sierra onto 1 SSD and 1 HDD. I have Windows 10 Installed on the ssd and I want that to stay like it is if possible. The Hard drive has 3 partitions right now one for Sierra, 1 for storage, and 1 I'm wanting to use for linux. How would I go about installing Ubuntu on the hard drive without overwriting the clover bootloader? Last time I followed the guide it overwrote the clover bootloader and I had to start from scratch on the Sierra side.

You make sure you get the UEFI installer for Ubuntu and install it UEFI mode. This puts a Linux folder in the EFI/EFI folder.