widening x-member

[68C15]

not long ago I asked about installing a '78 G body front frame in my '68. I was told the G body track width is 7" narrower than our trucks.
since then I have been thinking. what if a person was to cut it down the middle & widen it about 5". ( I am thinking that 2" would be good for room to turn wheels inside fenders.) granted I would need to make the center liks longer, no problem. has anyone else had this thought or tried it before? any engineers here that can help? (Jewels?) I really want the geometry & ride quality. I know there are places like Fatman & Heidts that have real nice kits, but I am kind of old school & like to fab. for myself.