Allen--
As a former Building Official (now retired) I provide this for your consideration:
--wood trusses are properly called 'Engineered Wood Trusses' for good reason--their were designed by Engineer for their particular span, loading and configuration.
--Any proposed modifications to engineered trusses should be re-Engineered before proceeding
--Suppliers who manufacture and sell wood trusses generally design them on computer, then a registered Engineer signs off on that design.
--I have run into numerous cases of trusses which have failed, or were about to fail due to Un-Engineered modifications
--I have also seen several cases of failed 'farmer' trusses where folks 'designed' their own trusses and they collapsed the first winter
--Many wood trusses may look simple but there are a lot of loads and loading to take into consideration in their design
My suggestion to you is to contact the truss manufacturer (generally stamped or marked on each of your trusses) or perhaps the structure was built for you & you know who that manufacturer is. Then explain your planned modification and see what they can come up with.
I am thinking you perhaps could have a new Engineered wood truss made which would 'sister' to the existing truss which could then be removed.
From my experience, truss manufactures are good to deal with to solve problems such as yours
Good luck Delky dave in WYO
