All of the comments are very valid, especially the one about being very careful!!!
Just one quick note for you all with regards to rear weights. If you fill the rear tires with fluid, please bare in mind that as the rear lifts, the centre of gravity of the fuid moves forward and lessens the effect of leverage. To explain this better, imagine a plumb bob hanging from the centre of the rear axle, now imagine the rear axle lifted by a weight on the front end loader, where will the plumb bob be haning now?
The best form of weight is either a weight over the back axle mounted on the linkage or cast wheel weights as these are no affected the same as fluid. Hope this helps.