well this thread in itself as you can see is these guys doing things on the cheap and putting old Parts together not buying the most ridiculously expensive (for what you get) part there is and putting it on their car.
I would almost bet that if both the cars were on jack stands and remember these don't jump out of the box and install themselves. If I had two 4ft one and a half inch by 2 and 1/2 in pieces of Steel I bet I could cut those three little slits in the rear and slide this in and weld it all in before you could drill all the holes to put that one in and get all the bolts to line up and get them all tight.
If you're lacking so much time that you don't have time to bolt-on parts that come in boxes that's just crazy. An hour a day? I couldn't imagine this taking more than one hour per side.