Most of the cruising jibs we made for the Mac26 classic were 105% LP and they fit beautifully.
The jib tracks on the Mac 26 classic (S and D) are on the cabin top, so the lower spreaders place some constraints on how far aft the leech edge can be without hitting the spreaders. That's an important design constraint. The only way to get a 110 or 115% jib to sheet to the cabin top is to make the clew very low to the deck.
We've made jibs as big as 115% that can be sheeting to the cabin top. However, in order to keep it from hitting the spreaders, we had to put the clew as low as possible to the track. A decksweeper is great for upwind downwind racing, but not very practical for general cruising. The deck sweeping shape makes it hang up on the lifelines on any point of sail other than a close haul. It also makes it point exceedingly well, but it not reach very well, due to the vertical sheeting angle.
And, even though some people think you can't make 135 on a 26C that works well, we built quite a few furling 130% and 135's that worked just fine. They were desgined to be sheet to the cockpit, but when furled enough the leads could be moved forward, for an effective size something smaller than a 100%
Judy B
Retired Sailmaker who made a lot of Macgregor sails.