We need more information. Why a new mast? Why farther forward if it is just a replacement or is it a rig re-design, by a qualified designer I hope?
Bought the boat without a mast which the previous owner trashed.The rigger insisted that the cap shroud should be in line with one of the chainplates of which there are 3 either side hence he insited I move the chain plate or move the mast! Neither of which seems a good option. I apparently could have running backstays but thats something I do not want as I will be sailing solo.
This is a new Selden mast and although I got assurances from Selden that everything is OK, because of the previously raised issues wanted to get opinions from the great sailing fraternity. I would hate it falling overboard in the middle of the Atlantic!!