FG-140D-POE-T1 upgrade to 6.2.2?

Hi Guys,

I bought a Fortigate 140D-POE-T1 for my home lab under the assumption that it was the same as the 140D-POE... the -T1 only supports 5.2 but I want to play with features in 6.x stream.

Can anyone suggest how to update these to a 6.x?