These are some of the best constructed subframes I have seen to date. Why? Because they are not massed produced by some company trying to make/save a buck when constucting them. One of the individuals that contributed to this article built and installed mine.
If you can weld and cut steel, I recommend building these are they are much better than any of the produced ones...
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Thank you..I have been wanting a nice set and was resorting to just building my own with the stuff i have in my shop. Thanks for the site!!
A couple of better diagrams..
One is rectangle tubing and the other is square.
Read the first link.. Pretty descriptive on the build and installation process.
Rex made and welded in mine. Best ones ever.

somebody make/weld in mine for free. i got a welder..and a lift.
they are pretty simple to do, my uncle and I actually figured out some through floor sub fram connectors with kickers for roll bar.
Looks easy enough. Also, if your worried about stress cracking where the plates connect, you could fish plate them instead of running a straight edge.