2003 Disco, 156,000 miles, Disco Mike's maintenance list completed. Ran great. Oil light came on at hot idle. Original oil pump outer ring broken into 5 pieces. , Oil pump/timing chain replacement started. Got everything off, timing chain appears stretched,, no sludge in oil sump. Ordered new pump kit, chain, gaskets, thermostat, hoses from BP Utah. Inside of crankshaft hole appears unscored. When attempting to install new gear set, can't refit outer gear into timing cover. It seems as if the gear is a tad to big. It should just drop right in. Is it a problem with the timing cover or faulty gear set? Thoughts?? Thanks !!