I found errors with the previous method, wasn't functioning correctly so I deleted everything and started again.
After 3 days trying to upload all different ways via FTP FileZilla, I decided to upload directly via my cPanel file manager, once files were uploaded I then used Chrome Incognito to install (Install_PrestaShop.html, index.php, prestashop.zip)
Which made it work! No changes to code whatsoever!
I think the trick was installing in incognito mode, but like I said uploading files directly to cPanel could have done it.
I've tried this twice now and worked fine both times.
Using PHP 7.0
Note: Back office link wont work in incognito when installs complete, delete the /install folder and then use normal chrome to access your domain.com/adminxxxxxxxxx