Congrats on the new 2538. I've had mine for a little over a year, and have no regrets. Does everything I need and more.
As far as the tool box, I mounted a medium size one on the cowl covering the rear fuel tank, and mounted it to the right of the filler cap. (My filler cap is on the left end of the tank). If Mahindra has changed it to the center mount, then that's a bummer. You don't need a huge tool box. I just put an assortment of tools, and supplies I might need to get me back to the garage where more extensive work would occur. Couple of crescent wrenches, screw drivers, channel locks, pliers,utility knife, bungy cords, tape, a little wire, and whatever else you might need to get back to the garage. My tool box is only 6"x 12"x 6" and it's plastic to resist the weather. Some guys also mount it on the fenders, but I used those for installing my cup holders.
If you do the prescribed maintenance and don't beat the **** out of the tractor you should have very little problems. Let her warm up sufficiently before working it hard, change the oil and filter, fuel filter regularly, and be sure to do the 100 hour service for the rest of the fluids. Take your cue from your dealer for anything else that they recommend.
A few points my dealer made to me:
Take the outer air filter off daily and tap it against your front tire to release the dust in it. Then blow it out from the inside with compressed air or leaf blower.
Don't work the tractor under 1500 rpm (FEL, PTO attachments, etc) Keeps hydraulic fluid pressure up and flowing.
Don't wash the tractor's engine unless its running. He told me not to wash it, but blow the dust off with air.
Good luck, and welcome to the forum !
Merry Christmas.