SSD Card compatibility / Windows 10 update

I have a Dell Venue Pro 10 5055 and have recently purchased an SS card increase Storage as the operating system and other files leaves me with only 3GB of memory left on my tablet.

I bought this for the sole reason of wanting to upgrade to Windows 10 (Currently windows 8.1). I downloaded the updater and I then says their is not enough memory on my device. Is there anyway I can select my SSD card to be the primary memory unit? I.E the downloader will use this SSD card to put the download onto, enabling me to upgrade to Windows 10.

I already know you can select the SSD card as a default device for media such as photo's ect but I've been looking around and even phoned up Dell support (Who were useless) and they said my SSD card can't be used as my primary destination for all downloads.

This seems incorrect to me, this essentially means I have to copy my C drive onto my SSD card to make room on my C drive for this Windows 10 download?

HELP.

Thanks in advance.

Tom