Cut the end of one shaft to your Specification, or as defined below.
We do not recommend butt cutting shafts before being installed in heads.
Normally, shafts are installed in head before butt cutting the shaft to playing length.
That is so the bottom of hosel bore, to ground distance, is included in the total playing length.
Generally, the bottom of bore to ground dimension(BBG) is 1-1/4" BUT NOT ALWAYS; check your heads for BBG.
Men's Standard steel 6 Iron length would arrive as 36 1/4" ( 37.5" - 1 1/4" ), etc.
Unless you tell us otherwise we cut .355 Taper Tip shafts 'assuming' 1 1/4" bottom of bore to ground dimension and no allowance for lie, or thickness of grip cap.
Hosel bore depths can vary, particularly after they have been reamed, or epoxy is drilled out, for a re-shaft multiple times.
Lie angle adjustment of heads can slightly change playing length and swing weight.
The thickness of grip butt caps vary, so we recommend not trimming to allow for the grip cap.
Note: when swing weight matching clubs,.. butt lengths might need to be different to get exactly what you want, with the grips you use.
Products we modify for you are not returnable, or refundable, unless we make an obvious mistake.