I have an 88 2.5L, 4spd, 4x4 and it is a good little rig. Even at the high altitude up here in Colorado I’m giving up about 20 horsepower, it still gets around good. The big advantage to the 2.5 is they get pretty good gas mileage. Gas is cheap right now but could be back up to $5 gal real quick… There are really no performance upgrades for the 2.5, down the road you could do a 4.0 swap if you are up to the challenge.
The ticking sound could be a cracked or loose exhaust manifold?