"I really do not want to cut the new spreaders"
Did you ever hear the old Bill Cosby routine about Noah and the Lord?
"Voompah, voompah, voompah..." Hey Noah, whatcha doing there? Building me an ark.
Really, it is OK to cut spreaders to length. On some boats the stock spreaders actually exceed the one-design racing rule
for the boat, so if you want to point higher than the other boats--you cut 'em down to the class minimum, no matter how they were built.
A nice metal blade, some sandpaper, and if you aren't handy with that, drop 'em off at a machine shop with explicit instructions.