I also create simple extruded squares that have the same dimesions as the truss i am ultimately going to use. Simply shaped symbols that reprent complex truss are faster to work with and easier to look at while spinning around in 3D, and can have bold colors representing their length.
Once everything is in place either use 'replace symbol' under properties and replace with the detailed truss symbol. Or 'edit' the symbol and swap the simple shape for the detailed truss.
3D rotation etc.. should stay the same.
This approach is handy for all hybrid objects that are trickier to rotate in 3D.
Hope this helps