If you use the long pin you will have to grind a small amount of, the short pin fits fine. They should need to be tapped in, I've seen some that are a little loose depending on the cam. I use a loctite product made for press fit items if I feel it is a little loose.
The TFS stage 1 cam came with long & short and the instructions said to use the short. I probably will put a dab of loctite in there just for peace of mind. I wouldn't want my beastly 350hp to cause any issues...
regular loctite will not do anything... you would need to use the kind that is made for press fitting. It has a primer spray then you apply the green fluid.