Switching out cabin

I had a similar post in another section but might be the wrong place. I have plans to build a Benford dory which Mr Benford helped me modify plans for more headroom (I'm 6'4") but I have been offered a 30' grampian that has almost enough headroom and I am thinking of replacing the trunk cabin with a raised deck cabin like in my plans and also refitting to the junk rig as in my plans. I'm trying to find links,books or any info on how to go about attaching the cabin to this hull and what stability issues I may have if I go this route. This would save time and money for me and I think I would prefer the fiberglass fin keel hull over the flat bottom dory hull. Any help would be appreciated.
Thanks,
Patrick