This also begs the question: What is the end goal of this street car?IMO, anyone should think long and hard about running a drag suspension on the street. Worst setup I've ever tried.
Pretty much ruins everything about driving the car.
My work van handled better.
Is it popping the wheels off the ground from a stoplight? (not hatin', I've always wanted to do this)
Is it launching fast out of the hole?
I'm suggesting that if the weight that you [don't] save by keeping the OEM k-member is properly transferred, that this may be a benefit for higher torque or lower geared cars. At any rate, taking that weight off of the nose as torque output increases will provide diminishing returns.
I would probably spend that money on the ass end of that thing even it's to invest in a better set of tires (or more of them since what you (OP) want will wear fast).