Making a 20' long boat 8' is a bit of a reach. You could probably do it and get a boat that works, but it probably would not be the best boat possible. There are other boats which would probably scale better.

: how small can i make the guillemot double their will be one person using it i
: would like to make it 8 feet long. is this a good i dear? why the double
: is it has the bigest beam at 28inch.So how close can i make the form?