I applaud your creativity and commitment to the project, but the question still lingers of why not pull the stick? Having recently done my 51, you are looking at ~$10,000 give or take, and something you are only doing every 10-15 years. In my case, it was a good time to rewire the mast, and put new sheaves blocks in. I also drilled out the sheaves and put in ruon lubricated composite bushings and all new forecheck and spreader lights. But if doing it in situ, I would suggest using a piece of amstel to measure each one out and just put tape indicators and the termination points? And then cut your new rigging. I had all mine swagger and used Haynes fittings. Some of the larger turnbuckle were I believe around $750, but they were beefier than the OEM. I did have to fabricate some 316 as shims to fit some of the chain plate pins, so I bought some 1 inch stock and spent some time on a lathe at work. Schaffer has recently entered the market and thet can custom fab stuff if need be...really good folks there. If you have SSB, the back stay fittings for my wire size was $2200 each for the ones I licked, so I opted for a G and M detachable for $400. Perfectly calibrated and 4 less connections on a critical piece of hardware. Good luck and keep us posted. This may be a good approach next time I do it...but WOW! I would really need to see the benefit since dropping the mast is a small fraction of the total cost. Good luck and following...thanks.
Howdy Wurzner and thanks for the input.... well I'm not foreign to pulling a rig....been there done that (not on this boat). Matter of fact the only reason I pulled rig, I had to go under a bridge before the yard, LOL. Second boat...was off Singapore on a mooring buoy. Replaced all rigging one at a time. That said, having worked in the oil patch for 15 years, being aloft is a piece of cake for me.

And, to top it off....the local yard here has this poxy looking crane/boom that they use off the yard hoist. I don't know....looks a tad scary to me! Needless to say, not sure if they would even attemp this rig....even if I let them!!
Eric below....has it down and was nice chatting with him on the phone (thank you again Eric)

, descibing his technique. Mind you...not for the faint of heart, Not (easy peasy)...but, diffinately do able.
Regarding sheaves... I visaulize no existing problems there as main sheave, is in mast furling. How many times has the main sail dropped and went aloft again. I would imagine not often....to warrant replacing my sheaves. Same for headsail.
Price point.... I would think (for my situation) would be considerable due to yard time. When I pull out, I'm in there for better than a week as I do my own work...this time I will be adding a 3D transducer as well as forward scan, add the mast time on top of that, not sure I could even endure the punishment. Bottom line, for me... heading for the South Pacific and beyond, I will know it's done right!!

and that my friend, is worth it's weight in gold!
Thanks for the heads up! Fairwinds...
Windswept H46 #028