Crooked frame crossmember?????

[Mark B]

On my 1970 swb c10, there is a heavy crossmember about a foot to the rear of the axle. It is very crooked! It is a U shaped channel, open to the rear of the truck. The passenger side is 2 inches more towards the rear of the truck. The crossmember is rivited to the frame rails and does not look like it was ever tampered with. And strangly, the same crossmember has a large triangular gusset on the top/driver side/front of truck side, but no matching gusset on the passenger side.

Does anyone know if this is normal? Is there a reason for it to be crooked and have a gusset on one side only? Is your truck the same? Or was my truck built by disgruntled assemby workers?

thanks everyone
Mark