You'll simply need longer bolts according to how much positive camber you want. You will also have to use a lock washer on the new bolts. Here is SOME information on this. Parts list for rear camber are from pep boys and Lowes.
Total cost for the rear $13.19 and about an 1 hour labor.
(8) m10 10.9 metric class bolts. m10x40mm and 1.5" long (pepboys)
(??) m10 washers perferably hardened, two per side, for every +degree
of camber you want.
(8) m10 slit lock washers
Tools needed:
14mm socket
17mm socket
car jack
3/8ths ratchet or whatever you have
the extension for the above ratchet
lug nut socket
2. Remove wheel
3. Un-bolt the 4 bolts on the brackets that hold the control arm in place using the 14mm socket + extension
4. Put slit lock washer on the m10 bolt then slide it through the control arm and then put the washers on the other side.
5. Tighten new bolts to manufacturers specs with the 17mm socket + extension (some bolts may vary in size) and repeat on all other 7 bolts from both wheels.
The most you should go is +3 dgrees depending on how low you're going with your suspension. The rear camber is much easier to do than front, as you can see by the kits shown.