Installing a 340 equipped with Eddy heads.

'64 Cuda said
In the past I've used lift plates with aluminum manifolds (not with aluminum heads, though) & never had a problem. Now, in my old age, I question the idea of lifting 500 pounds or so with 4 1/4" studs threaded into aluminum.

I had my doubts about them in my youth, the older I get the more amazed I am at what smaller fasteners can hold.