Perso i am not persuaded by the sequence AL choose . Seems common to all manufacturers. I built an AL Endeavor 30 years ago as my first build but even then i decided to finish the topmast and topgallant shrouds before stepping the masts. Just seems sensible. The more you work on the model the more you take risks, and working up at the top of the mast , where everything is thin and delicate while supporting the weight of your arms and watching out for everything seems to me highly fatiguing. And dangerous. Nowadays i rig everything i can "off model", sat comfortably on the couch! Endeavor has fairly simple rigging compared to a clipper, you can rig the whole mast complete with lower shroud lines, stays ,yards, sails, sheets , bunts , leeches etc before fitting to the ship without much problem. To attach to the ship i go foremast, main, mizzen then bowsprit. Lace your lower shrouds, (easy ,to find space , just flip your mainsail up out of the way) then fit internal pinrail running rigging,while there is space, then backstays( tension later with the forestays) then on to next mast. Three masts up then bowsprit . This is when you tension the whole rigmarole with the backstays and forestays working from outside to center, bottom to top.(carefully) Finish off with sheets, tacks and (bowlines on older ships )Haven't mentioned halyards because depends on the epoch, fit them in where they have to go ! That's my sequence and i'm sticking with it ! (small variations depending on the ship) If that sounds complicated then the AL system works too.