Tensioner needs a 15mm wrench. That'll relieve the tension so you can take off the belt. The same wrench will take off the tensioner pulley as well as the idler pulley. Pulleys run about $18 each. Single bolt for each pulley, re-use them. Doesn't get much easier than that.
While you have the belt off, start it and rev to 1500 to see if squeal remains without the belt. Rules out those two pulleys, makes it likely the CMP. Don't run more than 20 seconds or so with the belt off. No water flow=quick overheat.
2000 2.5 MO5D 4.10 one-wheel drive DD - gave to my older son
1990 STX 87 2.9 going in.....Junked it
2000 3.0 4WD M05D 4.10 S-cab Off-Road package with 235-75-15" tires, hotrod DD, lol