Background: I'm trying to modify my attic a little bit in order to store
some things up there. Currently I'm busy fastening 3/4" plyboard over the
ceiling rafters (so objects to be stored won't crash thru the drywall
ceiling). However movement/activity up there is hampered by the fact that
the roof is supported by factory produced 2x4 trusses, as these are composed
of many cross members that switch back-and-forth at oblique angles between
the upper and lower rafter sections of each truss. It would certainly make
my attic storage efforts easier if some of these cross-members could somehow
be removed out of the way (that is... in such a way as to not compromise the
structural integrity of my roof, of course).

Therefore I'm requesting feedback on the following idea: 'Sistering' (i.e.
reinforcing with) 2x6s to the topmost rafters, followed by removal of some
of the supporting cross-members of said trusses. Not being a carpenter or
structural engineer of any kind, I'm seeking informed comments/advice from
others before going further with this.

Thanks.

Ken