I have only just seen this thread,there were a number of companies doing 'Flat Pack' boat building kits & detailed DIY plans/designs in OZ during the mining boom, years ago as the normal boat manufacturers could not keep up with demand.I do not know if you have researched over there or whether those companies are still going but may be worth a look for ideas & methods of easing construction .
A number l know of up in the top of WA were basically what you are looking at ,they have to do beach launches so they were 5-7 mtr pontoon boats designed to be beached to unload etc .
Good luck with the build & make sure you take plenty of Pics & post keep us updated ,l love it when blokes have a crack at things like this
Bookmarks