One of the reasons that not as much is made for the '71-'73, as far as front end stiffening is concerned, is that the '71-'73 platform is substantially stiffened from the factory, if you check out how the '69-'70 Boss 302 front end used an additional lower a-frame connector piece going under the engine to tie the suspension in, you'll notice that on the '71-'73 cars, this is already done, welded in, not bolted, as part of the front clip, so we start out with a more stable front end than the earlier cars.