any thoughts about just having the framebuilder do a custom frame? how much cost differential would that be from the conversion. and theoretically the result would be better and more integrated and to purpose

I have had some discussions with a well known framebuilder who has done a lot of pioneering work with disc on road bikes. He noted that to meet his safety standards, especially the forks he has to build stronger and his disc frames are are heavier. disc vs caliper is all up to planned usage