The synthetic shrouds were all connected to the mast and ready to be tuned. The goal is to achieve a straight mast that is in column and centered over the boat.
At this point, the spreader position is not a significant concern. The spreaders will move around as you tune the rigging but they will not be a factor until later on. If a spreader appears to bend up or down significantly, then it must be rectified. For now, the main focus is the mast and the spreaders will simply project laterally from the mast.
The tensioning system was setup on both sides, allowing symmetrical adjustments to the tension of the stays and position of the mast. It is important to start at the top of the mast and get that centered over the boat before moving on to the lower stays. Remember to work top down, as it will make difficult problems seem much simpler to solve.
Once the top of the mast is centered over the boat, the intermediate stays are connected to the tensioning system and adjusted until they are true. The intermediate stays will cause an S curve in the mast if they are out of tension, so adjusting them will remove this odd bend that the mast can take on.
The next stays to be tensioned are the forward lowers. These stays will pull the mast forward and induce a bend into the mast (which is desireable). These stays are not under as much tension as the cap shrouds, but still more than the aft lowers. The purpose of the aft lowers is to correct any sideways bends in the bottom of the mast that might be induced by the forward lowers. These stays are the loosest of the shrouds and require very little tension.
All of the chainplates are rather inboard on the deck, so it was detrimental to run the lashings through the deadeye and over to the turning block, so instead, they were led from the stay to the turning block to the tensioning line. This produced the least amount of lateral pull into the equation and it was rather straight forward to gauge how much tension would be on the stay once the tensioning line was released and the stay was no longer being pulled in a lateral direction.