How to build multi-deck planes?

[beelzerob]

I've seen several very neat designs that involve two layers of fuselage, stacked on top of and heavily clipped into each other.  How is this accomplished?  I can't find any way to attach a fuselage to a fuselage, except end to end.

Thanks

[A_name]

What part are you using as a fuselage?

[beelzerob]

I don't have KSP handy, but any of the standard parts you'd use to build a plane...the fuel tanks, open cargo sections, or cockpits.

[OutlawFarmer]

Fuel tanks attach radially just perfect, you can fine tune them with the offset tool.

[max_creative]

Stack mk2 or mk3 fuel tanks on top of each other, place the passenger modules on them, and clip. Or use Decouplers, just don't Decouple them.