Re the front suspension, the fastest wearing part is the idler arm, position mirrors the steering box on the pside frame rail.
Crawl under and look at the arm and it's pivot shaft in the housing bolted to the frame rail. Have an assistant turn the steering wheel side to side, wheels on the ground for resistance, and see if the shaft of the idler arm wobbles fore and aft in the housing as the steering is turned back and forth. With a monster set of channel locks and a caliper, measure the distance from the tip of the stud on all the steering pivot joints unloaded and after compressing the stud into the ball housing. If the measured diff is over 1mm, replace those parts.
Lube the front wheel bearings, or replace, and clean and lightly lube (the spec calls for light oil) the autohubs, cleaning out any crusty grease. Also replace the little bearing where the cv axle outer stub goes into the back of the front spindle thingy. Replace that seal as well. Use a GN 3/4 ton front axle nut socket with all of the prongs ground off except two opposing to match the monty axle nut. Pay good attention to how it comes apart, and the screw retained axle nut lock ring. Many monteros have some front end wander from loose bearings. You can assess how much slop is up there by jacking the front wheel off the ground, and grasp the tire top and bottom and try with vigorous wobbling to feel any slack in the bearing. ANY slack requires adjustment, you should feel NO movement.
I like to replace any wheel bearings run loose. The slop makes the bearing run on the race on one side, and if you snug it up, the lack of clearance makes the rollers run on only part of the race, the rest being prematurely worn.
Test the ecu temp sensor now, and the icm too. The temp sensor controls fuel mixture. The icm can get an internal short and eat the ecu. Be warned. Do not use throttle body cleaner unless you plug the hole in the bottom of the bore.