Help adding Running Back Stays

[mrybas]

Hi,
I have a Tashiba 40 (aka Baba aka Panda) with a double spreader cutter rig. It has permanently rigged aft led intermediates to support the staysail. I would like to replace these with running backstays to allow the boom to swing out farther while sailing down wind. I have a rough idea of what the set-up should look like, but not sure of the specific parts needed to put the package together.
At the deck there are already eyes installed behind the aft end of the jib track that should be a secure location to terminate the running back stays on the deck end. At the mast end, I was hoping to use the current termination of the existing aft-intermediates. The current termination at the mast is a sort of 'T' shaped fitting. Can I keep this fitting, and cut the shroud and use a norseman/stalock fitting of some sort to attach to the new running backstay?
Thanks,
Mike
SV 'Hartley'