Box Rear Upper Control Arms

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	Ok, the idea is to take this stock GM A-Body 10-Bolt rear end control arm and Box it, and convert it into a 12-bolt rear end arm. A 12-bolt rear end arm can be used on 10-bolt rear ends but 10-bolt rear end control arms can not the used on a 12-bolt rear end. For a discussion on this topic see this link (click this text).
	First step has been accomplished. The arm has been cleaned up and the bushing has been removed. To see how to remove bushings see this link (click this text).
	Now we need to create a template of the piece of metal we will use to create the bottom plate to box the rear upper control arm. I placed the arm on a piece of poster board and traced the bottom outline. Then I cut that out and taped it to the arm and traced the rest of the piece needed. I cut it out and did a trial fit.
	This is just another view showing the end piece.
	This is what I ended up with. Now the trick is to turn it into a piece of metal. I happen to have a freind who has a Plasma cutting X Y plotter.
	So these are the pieces I ended up with. You could do the above steps yourself and save the dollars.
	Next step is to carefully bend the flat pieces so they conform to the arm. You want a nice fit so the pieces lay on the arm with no gaps. Note the pieces are slightly smaller than the arm. This leaves room to build up so weld bead so the weld is nice and strong.
	Just another view showing the end and how nicely the piece has been bent to fit the arm leaving room to build some weld bead.
	Ok, now we are getting to the good part. Clamp the bottom in place to insure a tight fit, and that it does not move around on you.
	Do not try and run a bead all the way around the outside of your bottom piece. Make small spot welds skipping around so you do not warp the metal.
	Now you can remove the clamps to give yourself good access  to finish your welding.
	Just another view showing the end.
	Now make small “stitch” welds in alternating positions to avoid any warping of the arm or bottom piece. You can also no see why the bottom piece is made slightly smaller then needed so that you can build a nice weld bead for strength. You need the extra weld bead when it comes time to grind it smooth.
	Welding is done and the beads have been ground smooth. The arm now has the appearance of being all one piece. Bottom view.
	Top view.
	Finial cleaning and now ready for powder coating.
	My new Powder Coat gun. It is a full 100,000 volt gun.
	My oven to bake the parts in.
	All done, ready to cool off.