glassing and fin question

HI

having only done 2 boards - i was wondering if  consideration is  made  as to  how far to foil out the blank in relation to the final glased board being 6/4 deck and 6 bottom - as in any compensation for glass..

as i remember from before what was shaped felt differemt once it was glassed basically just fatter somehow 

and centre fin placement wise : i was planning on setting that 5.5 up from the tail to the start of the box whould that be about right - its does not have hull like contours 

many thanks