I've just been making my own magnetic plugs since some of the deuce plugs get to be a little odd sized and hard to find (Differentials, Transfer Case, Transmission, Engine). When I do an oil or fluid change I take the plug off and mill or drill a pocket the same diameter as the magnets I get (usually 3/8 or 1/2" diameter), then press the magnet into the hole.....Or even just putting the magnet on the end of the plug should be fine, the pocket just makes me feel better since there is less chance of the magnet moving.
You can get magnets from places like Mcmaster.com but 98% of rare earth magnets now come from China or chinese owned/controlled mines so you can easily get some easily and cheap from ebay.
Just search for something like this: RARE EARTH NEODYMIUM DISC MAGNETS 3/8" the thicker the more pull they have. I like to use 3/8" diameter by 3/8" thickness which has about 8 lbs of pull. You can get them in packs of 10 for less than $7 shipped. The higher quality ones (like Mcmaster sells) withstand higher temps like 300 deg F, the lower quality ones start loosing their magnetic pull at about 180 deg F
INTERESTING MAGNET TIDBIT: Since China controls 98% of all magnet production, the US is attempting to open a Strategic Reserve for Rare earth magnets since there are in so many things (including most of our country's weapon systems). China has been scaling back production of the magnet manufacturing to control prices similarly to what OPEC does with oil production and Debeers does with Diamonds. The US closed its last mine about 10 years ago, and is trying to open one back up. It might already be open on a small scale, but I know its been a real battle since its in california and all of the environmental stuff to deal with. In my job, we purchase lots of Linear Servo motors which use a ton of rare earth magnets in them. One of the larger motors jumped overnight from $28,000 to $40,000 due to magnet costs.
