Subframe Lockbolt install:

13.) Lower your Subaru WRX/STi until the weight of the car rests on both tires. You can use tire ramps since they are great, because they maintain some space under to access the bolts.

14.) Torque all four of the rear subframe bolts to OEM spec which is 96 lbs-ft.

15.) Torque the two lockbolts to the lockbolt manufacturer’s spec. This is usually somewhere around 60lbs-ft.

16.) Double check that each fastener is tightened that you have touched.

17.) Lower your Subaru WRX/STi down onto the ground and clean up. Make sure to test out your Subaru to feel any differences.

18.) Make sure you get your rear toe settings checked with a alignment. If the rear subframe had to be moved around the toe setting might have been altered which can cause bad handling and increased tire wear.

You can buy Lockdown Bolts here:

Kartboy Rear Subframe Lockdown Bolts Subaru Models (inc. 2002-2007 WRX / STI)

Whiteline KSB750 Rear Subframe Lock Bolt Kit

Tools:
17mm 6pt socket
Ratchet
Socket extension
10mm Allen socket
12mm x 1.25 tap and tap socket or 12mm x 1.25 Thread chaser
Some type of thin brush (bottle brush).
Torque wrench
Prybar
WD-40 
Anti-seize and some grease
Tire ramps
Jack and jack stands