Chainplate rebedding with mast up
I need to rebed some chainplates on our "new" boat. I've done the procedure before on this boat, but the mast was out.
The part I need help with is the "mast up" thing. My shroud configuration is the standard single spread rig, with fore and aft lowers (3 chainplates each side). I've been told I can run the main halyard to the rail, then mark the turnbuckle position with tape, and remove the shroud to do the chainplate. This makes sense on the upper, but what about the lowers? Can I remove those (one at a time of course) without slacking the lowers on the opposite side? The main halyard will support the top of the mast, but not the middle where the lowers attach.
I just want to make sure that I can safely remove one shroud at a time, replacing before moving on. Or do I need to take some other precautions?
For what it's worth I'll be doing this at the slip on a calm day (it's well-protected where the boat is).
Thanks for any advice you may have on this.
1984 Sabre 34 Mk I