Good Morning

You might want to check the engines compression. On some of the 1992-94 engines the pressure relief valve in the oil pump would stick resulting in excessive oil pressure. The high pressure causes the lifters to pump up and the valves remain open. The engine suffers from a temporary state of No Compression. There was a little known blurb in some of the "Diagnostic Literature" circulated through the dealerships at that time. A replacement valve was/is the cure for this temporary setback. The replacement is easily identified by a shoulder located on the end face of the valve. The modified end eliminates the sticking problem at the bottom of the bore in the oil pump housing.

If you discover the engine has no compression remove the spark plugs. Place a battery charger on the battery and charge to full capacity. To avoid unwanted damage to the vehicle/you/or the ignition controllers electrically disconnect BOTH EZL ignition control units. Once the battery is fully charged begin cranking the engine at 1 minute intervals. Allow the starter motor to rest for 5 minutes after cranking for 1 minute. Alternate this process until compression returns. This may take an hour or so.

If I remember correctly the 140 chassis was more challenging because the location of the oil pump. You need to drop the sub frame in order to remove the main oil pan to gain unobstructed access to the relief valve.