My Son has a plow on His 4 weeler and the plow is fiberglass and real light,He was having a problem with the plow riding up and over the snow.
He installed a big chunk of steel with some bungie cords.
Today He wanted to do some repairs on the lift eye of the plow and while He was working on that I fashioned up these 2 pieces of 1 and 1/2" square tubing X 16",made a plug for the ends and welded one plug on and poured the tube full of lead then welded the cap on the other ends the welded them to the back of the plow frame.
Seems to be just the right amount of weight as He plowed from My garage door to the street and was actually getting down to gravel,of course the snow was only a couple of inches deep and was`nt packed but I was impressed with the way it all worked out.
Here`s the weight installed.



And here is the improved lifting eye.