Good evening Keith. Wow! Those are big sails compared to what I am used to. However the design and principle still stands so here goes.
First, I don't know where you live or sail but will assume it is the USA. Wishbone battens are much more efficient for sailing upwind and giving drive on a broad reach than straight battens but the compromise is their width. Assuming your sail mounts on the usual port side of the mast I have done some quick sums. The point of max width of your main will be about 6'3" back from the luff. The same for your mizzen will be about 5'8" back. The actual widths at this point will be 5'3" and 4'9". This may well block the port side of your boat from forward access on that side while at anchor. If you can cope with that then I'll continue.
The battens are fixed centrally at the luff and leech to the batten. The sail actually holds the batten up. The battens merely give shape to the sail. Despite this unusually wide frame the battens will and do sit level and horizontal. When the wind presses the sail against the mast the battens sit flat. When the wind blows the rig away from the mast it still sits flat. I have worked my sums for a sail camber of 1:8. I assume yours is a heavy boat so it will need the drive. But this camber is only 1:8 at the boom. It gets progressively smaller as the battens rise up the mast and the top panel might be 1:15 or so. This is down to a simple triangle drawn from the boom width to the mast top for the 'lazy-jacks' or boom lifts. So in other words, if you design the width of the boom then apply the triangle you can measure the width of each upper batten. The reducing camber as you reef is exactly what you need in rising winds.
Battens for a sail of those sizes will require larger sections than the ones I am using. I am no engineer but my 1"x1/2" rectangular aluminium tubes are good for up to 250/275 ft2. So yours should be at least 2"x1" tubes. The battens are not actually highly stressed.
Battens of this length will need some pre-bending to shape towards the luff only. The only alteration to the sail is the need to fit a cheap plastic grommet at the 30% sail point at each batten to allow the sail to slide across the batten-tie-rod. This is a S/S rod fitted through the side of one batten half, through the sail grommet then through the opposite batten half. The rods are drilled then fitted with S/S split pins. This balances the stress across both battens when on the wind.
Your boat may well have traditional Junk Sheeting. I now use single line sheeting but with sails as large as yours you will need multiple blocks between the boom and the deck. I also use downhauls on the boom, batten 1 and batten 2 as coastal sailors like me rarely need to take more than two reefs.
I hope this encourages you more and answers some questions. If not, write again.
Paul