After the new bike is built up, I'm going for a professional fit.
For me, the most complicated part of it his the stem.
Cleat and saddle position are adjustable. Handlebar position is a
function of spacer stack and stem angle and length. Spacer stack can
be adjusted. Angle and length are changed by swapping out the stem.
I'm going with a particular stem:
https://shop.fullspeedahead.com/en/stems/road-gravel/ns-acr-stemThe angle is fixed, so spacer stack becomes important. What I can't
determine before the fitting, is the length.
I don't think a fitting requires proper headset bearing preload. I
think I can use whatever headset the bike fitter wants to swap in
and out, clamped to the uncut steerer, for determination of
position. After that, I can purchase the right length of the stem I
plan to use, and only then, cut the carbon steerer.
What do you think?