Welding some brackets in pickup box question

I need to get some sand bags to weigh down the back of the newly purchased Mazda B2200, for the winter months. I would like to get one of the box liners with the slots to put 2x4's across to stop slippage but I can't find any used ones and I am not going to plunk down a ton of money for a new one. My question is, has anyone here welded any brackets onto the inside of the box to create a barrier to prevent movement of load? I don't know what the box is made of but I would assume it isn't aluminum.. What else could I do to create a "dyke" ?
Ideas.. Thanks...

If you're looking for cheap and not pretty, how about bolting a metal joist hanger on each sidewall and then drop a 2x6 into them. When it's not needed just lift the board out of it's slot....

Put one sandbag in each forward corner of the cab. They won't move around. Why screw up the bed for no reason.

4 patio stones.

If you want a less intrusive, but less robust, solution you could just put one of those tension shower rods across the bed (or something similar).

If you could find more trucks like that for that price, you could get rich selling 'em down here!

I keep 1-2 old tires in back of my PU. They don't move around much (at all). And whatever i put in them (sack of groceries, jug of drained oil, etc) stays put as well.

Another way....

put a couple of 2x4s lengthwise in the bed from the bulkhead to the tailgate. Put a couple of cross pieces in place to hold those to the width between the wheelwells. Then fasten a board across the top of them wherever you want it to hold the sandbags in the rear of the bed.

No holes required in the bed - but it would be bulky and more trouble to remove and store....

I second Joe's second idea, but six patio stones still gives you the option of piling crap you want to haul. if a patio stone is 2 feet square, six would do nicely.

6 full size patio stones is too much in a mini pickup. 2 at the front and 2 right behind them over the wheels is what you need for normal driving. I think you'll find that a 24 by 30 weighs closer to 70 pounds.

No guarantees, but a sand bag has a lot higher centre of gravity than a patio stone and unless you chain them down they're coming forward if you stop fast. Frozen sand somewhat resembles concrete last time I checked. I plowed snow commercially with a 1 ton 4 by 4 for years, and all of our trucks had patio stones. I've had some hard enough impacts to bouce the back wheels off the ground hitting frozen banks or drifts and never moved a patio stone. As I say though-no guarantees.

How about one of these? Lock any load in place or remove it altogether. You'd need only one to keep the bags from going forward, they'll never go toward the rear.

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