Possible - Yes.
Easy - No
SFF often use proprietary power and front panel wiring.
Somethimes you can find adapter cables for these on amazon /ebay type sites. Other times you must mod these yourself.
I suggest everyone not to use SFF prebuilt systems for just this reason. They always want to start gaming and then run smack into the sff limitations.
Lastly, one of the limitations is often the 35w power limit on the pcie slot so you can only put in a low powered gpu 🙁