I tried to install it to my E Drive which is a 1 terrabyte hard drive but it initially failed as it ate up the 10GBs free of my SSD in doing so.

Here is what I did next which worked (note C drive is SSD)
- copied the directory C:\Program Data\Package Cache (from memory) to the E drive
- deleted the "Package Cache" directory from the C drive
- put a junction point under C:\Program Data for "Package Cache" pointing to "E:\Package Cache"
(using this technique: http://sim-outhouse.com/sohforums/sh...pace-by-P38man)
- ran the install program again.

Could have also simply copied my planes to the e drive, deleting them from the c drive and then pasting back later but would have taken longer.

Hope that helps someone.