Sorry I have not replied sooner. I have been really busy and want to help but have not the time to get into all the specifics of diagrams.
Tim and Don have provided some good advice. Have you made anything out of fiberglass before? If not I'd suggest getting a little practice in before you tackle a bracket. The molds are fairly simple however the design and structural integrity are very important.
If you like tinkering around and time on the water is not a factor then go ahead and make a bracket. Make sure you take it out a bunch of times before you put the wife and kids on it
PM me and I will give you some measurements...just give me a couple days to respond as I'm not on the computer that much these days.
strick