Exams finally out the way back on with some building...

Dont like the chain setup so am going for a gear reduction using the following parts from technobots
Steel Spur Gear MOD 1.5 12 Tooth - Part No: 4715-012
Tbot Steel Spur Gear MOD 1.5 60 Tooth - Part No: 4715-060
Tbot Steel Spur Gear MOD 1.5 12 Tooth - Part No: 4715-012
Steel Spur Gear MOD 1.5 36 Tooth - Part No: 4715-036
which i believe will give me a 15:1 reduction?

How easy would it be attach this motor to this gear? I think the shaft diameter is 8mm as is the bore in the gear so would i just be able to screw it straight on or is it not that simple?