Last year some one posted a photo of a cable type engine strap that was available on a very few C-bodies in the early 70's. I went to my local rigging company (Denver Wire Rope) and spec'd such a strap for my Fury. Once installed you can't see it so it will be great for the purists. The device is made out of 3/16" stainless steel cable that can support over 5,000 lbs. See the photos below:
I simple bolted the top hole to the top motor mount hole with a large washer and the bottom to the motor mount bolt at the frame. No welding, can't be seen, lightweight, and it works. Cost? $16.57 in Denver. !drive