V8 swap motor mounts for AMC 6cyl crossmembers --

This product appears to be for AMC Eagles, Gremlins & other cars which came with the AMC inline 6 cylinder engine for which a V8 swap is planned. I would like to know if these motor mounts may also be used for a 258 equipped *SJ* such as a Cherokee Widetrack (which otherwise looks like a Chief).

I have the frame stanchions (frame horns?) from a 360 equipped SJ, and I'm planning on putting in a rebuild 401. Would this part make replacing the frame horns unnecessary?

Thanks.