Any reason for going for a Core i7 2600K over a Core i7 3770K or even a Core i7 4770K(will need a different Shuttle though)??
How much are you getting it for??
Regarding the GTX760,I would avoid the reference ones as HT4U found they had huge throttling problems on an open air testbench.
As with any SFF case,the coolers with the huge heatpipes can have clearance issues.
Edit!!
BTW,I have the the 500W SFF PSU which the R5 and H7 series use,as I converted an older Shuttle and used it for a while.
It is one of the best SFF PSUs made and one of the most powerful as typically they are under 500W. If you look at the reviews I linked to,a GTX680 or HD7970 will run fine on it. I know my 30% overclocked HD5850 1GB was OK with it!!