It seems to me like the best subframe connector would be the ones that protrude through the floor. You get a full box frame made of nice thick steel AND its tied to the floorboard. Best of both worlds IMO.
Agree w/ this. welded front and rear, protruding thru the floor and welded full length in
the floor. driveshaft loop welded to both. I bought the 2" sq. tubing for $18.00 , cut and installed inside the frame rails. Is sticking thru the floor about 3/4", used 3/4" foil faced foam board insulation to level the floor for new carpeting, u cant tell their even there.