Going to subframe connectors, you must run solid body mounts in the rear mounting locations at a minimum, but you should really do them all.
I like the chassis works subframes myself. They are a bit more expensive, but they provide a front mounting solution that is better than drilling into the frame and bolting, but still allows you to remove the sub-frame if required.
They work on the same premise as a hitch and receiver. You weld a receiver to the subframe, then slide the end of the connector onto that receiver and bolt it in place. In this way, the bolts are not structural, they just immobilize the connector on it's forward position. This also means that you don't have any protruding surfaces below the subframe. This gives you better ground clearance and should you bottom out and drag, you don't risk tearing the connectors out.
If you decide to add more grip and more power to the car, there is a cross brace with integral drive shaft loop that can be added later as well.
https://www.cachassisworks.com/c-530...gm-f-body.aspx