What is the difference between the ls7 lifters and NEW GM Performance Parts Hydraulic Roller Lifter for LS-Engines
#SD8689
Can these lifters be used with the factory rockers

 

As long as they are not solid lifters you should be alright using them. It is a "stock" replacement. I have not seen them side by side however, so it is a shot in the dark, but I bet that they would work just fine. Most of these parts are interchangeable across the LSX platforms.