Molding/trim concealed slide-on system

A building trim assembly for slidably attaching trim pieces to a building mounting surface of a building wall in a manner that permits the trim pieces to be slidably removed from the building mounting surface, the building trim assembly comprising:

• (a) a first piece of trim, the trim being elongated in a longitudinal direction;
• (b) a second piece of trim, the trim being elongated in a longitudinal direction;
• (c) at least two wall mounting strips for attachment to a building surface, each wall mounting strip having multiple spaced apart screw clearance holes for receiving screw fasteners for attaching the wall mounting strips to the building surface, the spaced apart screw clearance holes being spaced apart by substantially six inches or eight inches and existing in the wall mounting strips when they are not attached to said building surface;
• (d) a first elongated backside keyhole strip attached longitudinally along the first piece of trim, the first backside keyhole strip having a series of spaced apart keyhole slots aligned laterally across the said first elongated backside keyhole strip perpendicularly to the longest sides of said first backside keyhole strip and extending entirely through said first backside keyhole strip, the spacing of the keyhole slots being identical to the spacing of the screw clearance holes in the wall mounting strips;
• (e) a second elongated backside keyhole strip attached longitudinally along the second piece of trim, the second backside keyhole strip having a series of spaced apart keyhole slots aligned longitudinally along said second elongated backside keyhole strip parallel to the longest sides of said second backside keyhole strip and extending entirely through said first backside keyhole strip, the spacing of the keyhole slots being identical to the spacing of the screw clearance holes in the wall mounting strips;
• and
• (f) a plurality of attaching wood screws for insertion through the screw clearance holes of the wall mounting strips and into the building wall to mount the wall mounting strips to the wall, the wood screws having a pair of spaced apart screw heads forming a shoulder configured to set the depth the screws are engaged in the building wall.