The other big component of the performancepac is the set of 1.85- ratio rocker arms and corresponding valvesprings. They simply replace the stock components and the procedure is pretty darn easy. | 
The rocker arm swap requires access to the valve covers, which necessitates the removal of the large, plastic engine cover. It is held down with a series of ball-tip studs, so a firm tug upward is all that's needed to remove it. | 
Next comes the removal of the top section of the valve covers-one of the design details that makes working on ls engines easy. |
Another great service feature of the ls engine design is the stand-mount rocker arms, which allows the arms-after they're unbolted, of course-to be lifted out of the engine in one, swift motion. | 
A side-by-side comparison shows the subtle difference between the stock, 1.7-ratio rocker (left) and SLP's 1.85-ratio part; note the different oil hole at the top, which denotes the SLP part's different fulcrum. | 
Prior to installing the new rockers, they should be pre-oiled, such as soaking them briefly in a cup of motor oil. |
Next, the rocker arms are placed on the factory mounting bracket. | 
Thread locker is used on the mounting bracket studs. | 
The rocker arms simply drop back into place in the opposite manner in which they were removed. |