TH350 into stock 58 Chevy

[a58chevy]

I posted this a long time ago but unfortunately life got in the way of my plans. I am now at a point at where I need to start working on my truck again. I'm looking at going auto. The truck has the original 283 v8 (warmed up to about 300 horse). It currently has a tremec tko5 speed that I have decided to sell back to a good friend that originally sold it to me for the same price. I have a rear trans crossmember already installed but I know I might have to remount it.
Anyone have a pics or can someone point me to another thread.

Doing research I see just a trans crossmember like the one I already have advertised as a auto trans crossmember. I was thinking maybe i need to use the tranny cross member I have and purchase a engine mount crossmember?

Any help is always appreciated!