Strop for temporary stay or shroud

[seawolf]

Hello all,
Is there a simple and safe design for a strop to put around the mast to accomodate a temporary stay or shroud on the mast for emergency jury rig, or replacement and maintenance on the standing rigging.
The temporary stay or shroud will be made of wire rope with thimbled eyes in the ends, and a handybilly. The idea is to use a shackle connection from the strop to the wire and then to the handybilly which will be secured to the stemhead, or chain plate for tensioning.
The mast is aluminum and deck stepped at approximately 30 feet high for a 29 foot Columbia.
Sound and safe input appreciated.
Seawolf