That block covers up the intake manifold coolant passage. Usually one of the ports has a nipple with a hose attached for coolant flow in order to warm up the intake manifold. Seeing as you have all the ports plugged now, replacing the block with a flat plate should provide no functional change.
Just had to comment. I had bad luck with a Fram oil filter. One time when removing one, a long string of adhesive was hanging out the filter discharge. The adhesive is suspected to have come from the internal filter construction. If it had fully broken off, it could have block a critical oil passage. Suggest using Wix, Mortorcraft, or anything else.