Roof rack weight distribution for an Adventure Hull limits.

I currently am working on new roof racks on a 2nd vehicle for the Adventure.

The supports will be 2 carpeted 2x4 boards with the gunnels of the boat resting on the 4" part of the 2x4. Supports will be about 44" apart - illustrated below, trying to get the widest, flat areas of the gunnels.



Main concern is providing enough support for the hull so as not to distort it while transporting. Don't want a banana shaped hull .
My front and back tie downs won't get over torqued as the most of the anchoring will be around the hull and to the roof rack.

I've done this OK with a pair of Sports, but they weigh less and are under 10feet long.

Actually the hulls I'm using are for the Island but the same engineering limits should apply.

Any official Hobie insights?
Any thoughts or experience on this.

Just being a little cautious here.

TIA

Yakaholic

When I first put my Adventure on my short bed truck I only had 32 inches between the post. I tried to tie it front and back, but I felt i could have bent it in half without any pressure at all. The front and back straps were of no use being that loose. I ended up getting a trailer hitch post and that gave me three support points with a gap of 10 feet. I can now tie it front and back without any fear. Don't think I would trust 48 inches much over 45 mph.