As easy as changing a lightbulb mate. Take off rocker covers (6 small bolts), unbolt the old rockers (1 bolt each), lube up the new rockers (use plenty), using NEW BOLTS ONLY, bolt the new rockers down to torque (i THINK its 20nm plus 90 degrees, using loctite on the thread), replace rocker covers. DONE
If you don't have new rocker bolts, get yourself some cap-screw bolts from any bolt place for less than $1 each and they can be reused as many times as you want. The factory bolts are torque-to-yield and they stretch when torqued down, so one time use only.
EDIT: Actually mate go through this, How to install rocker arms/pushrods , all you need to know.
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