SILVERADOSS

Hi, I just removed the water pump on my 02 LS2 . I have new aluminum gaskets that came with the new pump.They have the o rings installed on them.My block has o rings on them that fit into milled grooves.Looks like if I remove the factory ones & install the new gaskets, it doesn't completely seal where the grooves are milled. Should I install the new ones with the factory ones on.the block? Or is there another way of doing this correctly.I appreciate any help.Thanks, Dan