carry roof top canoes on gunwales ?

I have 3 Wenonah: Rendezvous, Solo, Advantage. Too wide for the E250. I have carpentry skills for mounting hulls on gunwales side by side then securing the pack.
Is the gunwale carry, foam cushioned if necessary, structurally safe for the hulls ? No off roading, Interstate, no La.

I have car-topped multiple canoes on their sides without incident quite a few times, but they have usually been Royalex whitewater boats.

I have had my composite Spirit II and Wildfire on their sides on my rack a couple of times. Not my preferred way to carry those boats but it worked.

Packed and ready for vacation.

I wouldn’t think twice about doing it with Royalex.

SUPER. a second method is ‘3’s a crowd’ or ‘ima slob’ … scene in backyards.
One canoe goes upside down on gunwales(?). next rest or possibly nests over the upside down keel with bottom gunwale on ground, the third probably the widest longest rests top gunwale on second hull keel with lower gunwale on ground.
wonder if the slob spreads pressure more widely than ‘on edge.’
My on ‘edge’ idea was gunwale support at 2 thwarts with hulls strapped n caged with a braced frame.

any slobs in town ?

Todays idea ! assemble 2-3 1x4 truncated triangles bottom 2x4 running on rack slightly wider than roof:
Self drilling lathe screw 1x4’s tieing 2-3 together bow-stern
Block the top n bottom horizontal members with vertical 1x4 at starboard
Haul type strap (Walmart) canoe to vertical 1x4.
Add and space away 2nd set blocks n verticals for 2nd hull gunwales.
Wishfull thinking is suspending hull over bottom gunwale foam with road access adjustable haul straps possible.
Bought silicone paste. Lumber curing.