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PROJECT UNDER REVISION. PLEASE DON'T ATTEMPT THIS AS IT ISN'T WORKING PERFECTLY FOR ME.

This modification is for better suspension geometry setup and better handling. It involves shortening the L series control arms to fit the MY and fitting new custom radius rods.

First off I will explain how this mod makes your car handle better. The camber on a stock MY (Brumby, Brat, Hatchback) Subaru has about 1 to 2 degrees of positive camber. This means your wheels look like this from the front of the car \-----/ which is bad for tire wear and handling. See, when you enter a corner the weight from on side of the car is shifted to the other sides suspension thus giving body roll. When you have positive camber this means your tire around the corner is tucking itself under the car and pulling on the bead of the tire. This creates bad wear problems and also gives less rubber on the road around that corner then if it were negative camber.
The "Radius" is the angle at which the shock absorber leans to either give negative camber or positive camber while turning. On a stock setup on a MY Subaru this is set as negative. Which means while at full lock the 1 or 2 degrees on positive camber turns out to be more like 10 to 15 degrees. This really gives horrible tire wear and also can cause the bead to come unset while doing stupid stuff on sand or dirt.
If the wheel has 0 degrees of camber and the shock absorber is perfectly upright you wheel should stay upright at all times in relation to the car. But because the car will lean (body roll) into a corner you want to get more negative camber on the wheel in relation to that car so it is upright in relation to the road. Thus getting more rubber in contact with the road around sharp corners. To do this you need to set your shock absorber to have more positive radius. You can either do this by moving the top of the shock backwards in the car or move the hub forwards. I done this by changing the control arms and radius rods to move the hub more forwards. This also give a better entry angle and more clearance for larger tires. Here is how I done it.

Now for the acutal process. The EA82 control arms are longer and straighter then the EA81, as you can see in the picture.
The L series is 30mm longer when taking into consideration of the angles. Because nothing is equal, i.g my Brumby is bent, I had to make each arm a different size. The left side needed to be about 20mm longer (yes, 20mm!!!) To get the exact measurement we needed for the arm we first measured the legnth from the ball joint to the top of the strut tower. Remember, you have to do this again for the other side, both sides on mine were completely different. Then with the wheel attached and the car on the ground at normal ride height you measure 150mm on the wheels hub using a small ruler square with inbuilt spirit level, pull the bottom of the ruler square away from the wheel until the spirit level is, well, level! Now using plain steel rule measure the distance between the bottom of your 150mm mark and the wheel. This measurement, just say it be 5mm, now has to be worked out for the full legnth of the strut. For this you'll need to divide youre strut length by the 150mm then use that number and multiplie it by your gap measurement. So say strut is 720mm long then it's 720 divided by 150 = 4.8 x 5 = 24mm. So your EA81 control arm needs to be 24mm longer.
Because you only want the wheel moved forwards (this is the radius/caster mod) 25mm to 50mm you'll still want an angle on your arm. And because EA82 control arms are straight you'll need to cut and angle out of the control arm. The approximate angle you want is around 10 degrees facing backwards over what the EA82 arm is. To gain this 10degrees you will need to cut about 8-9mm more out of the rear edge of the arm then the front. This will also shorten the arm conciderible. After doing the angle wedge cut then bend the arm so the cut closes up completely. Now measure the distance between the engine crossmember mount side and the balljoint mount side of the EA81 arm and do the same with your newly bent EA82 arm. Now using the measurement we figured out you need to cut out enough of the bent EA82 arm to make them that measurement longer then the EA81 arm.

The arm then needs to be tested.You'll want to spot weld it so it doesn't twist. Bolt it in, and lower the car gentily so you don't bend it. Now do the same measurement on the wheel hub like we did before. it should now have a gap at the bottom (giving it negative camber.) You can calculate the degrees of camber by using the gap you have and the 150mm measurement your measuring and using the inv-tan function on a scientific calculator. What you need to do is divide the gap you have (just say that be 1mm) by the 150mm your measuring over. Then use the Inv button then the Tan button. This should give you 0.3819 if you use 1mm. That 0.3819 is your degrees of camber, in this case it's negative camber. Optimal negative camber for a road car is somewhere between 0.5 and 3 degrees. Some race cars go for more, but this will give badly uneven tyre wear. I've gone for the closest to 0degrees camber without being 0. This is because I don't want it to change over from positive camber to negative while turning the wheel. And the reason it goes from positive to negitive is your caster. But for now, we'll just get on with welding up the control arms.

After your cuts have been made and the arm has been tested weld along the seam of the cut. Weld the backside. Plate the it with 3 to 5mm steel for strength and weld thoughroly. It shouild look something like the image just above.