Whether you are a backyard board maker or a full production board factory these systems will work for you, and your customers...
'Do It Yourself' was the main driving force behind the plug concept. The plug system is pretty straight foreward to fit, especially if you have fitted a leg plug. Flatten any V under centre fin position first before glassing. Using a 15mm diameter holesaw blade, marked to 3/4" depth with masking tape, drill 2 x holes the same length apart as the fin base slots.
The closer the holes are to the bottom of fin base the stiffer the fin set up. Recommended settings are on the T shape at front of fin, and halfway at back slot. This can be done to a finished surfboard as well as during construction, although I suggest after glassing, under or over filler coat. Two layers of extra 4oz cloth under plug area will give good support before drilling, particularly on lightweight boards. Partially thread screw on each plug before fitting for ease of handling and ensuring resin doesn't drip into threadhole. Masking tape surrounding area. Sand flush when set.
The mini box will need a jig, although careful cutting with stanley blade ( and hole saw blade at front and back of stringer to remove wood) at 3/4" depth can be effective.