Replace Ubuntu with Zorin on second HDD

I have a question that you can help with. I have windows 7 on the primary HDD and have installed Ubuntu on a second HDD. I used easyBCD to set the boot screen. I want to replace the Ubuntu on the second HDD with Zorin and need guidance in doing this. Also what do I do with the easyBCD in order to fix the boot screen?
Thank you for your help.

I would leave EasyBCD alone, disconnect Windows HD, attach HDD2, and boot off Zorin to install from live mode, backup your Ubuntu /home folder first, then using Gparted in Zorin delete the partitions on HDD2 and then run the install to HDD2 from live desktop. Shut PC down, disconnect HDD2. Boot into Windows and then edit EasyBCD and delete entry for Ubuntu. Power down PC attach HDD2and reboot. Now in Windows launch EasyBCD and create entry for Zorin, save settings, cross everything and reboot.

Thanks for posting this. I've been trying to figure out how to install Zorin on a second 320GB HDD on my desktop system, the primary 2TB drive has a copy of Win7 that I cloned from the 320GB drive. I stupidly "upgraded" to Win10 last September. The constant updates from Microsoft have broken the system at times, which is why I installed Zorin on a circa 2011 HP Elitebook which dual boots with Win10 on it to try it out. I swapped the cables around on the 2 drives and managed to install Zorin to the smaller drive but it wouldn't boot after I moved the cables back. I understand that the MBR needs to be updated but I'm afraid to attempt it.

If you installed GRUB on the smaller drive that should be fine. EasyBCD backs up your existing Windows MBR/GPT before you make any changes to your windows boot sequence.