Solid Roller Lifter Question

I'm putting togather a 410" SBM with a Comp Solid roller cam and Comp 828-16 solid roller lifters. My question is, do the link bars have to be down facing the block?? or can they be run flipped with the link bars facing upward?? Facing down is going to require some grinding!! Any help would be appreciated. I'm ready to put this sucker togather, but had better wait if I've got to do some grinding!!! Thanks.