I just did the 50 hour engine and hydraulic oil services. One suggestion I haven't seen posted before is to have a spare hydraulic drain plug washer. Mine has a rubber seal at the ID which was peeling off a small thread. I reused it, but would have replaced it if readily available. Also, get the 2 strainer "O" rings. I didn't need them, but why get held up if there is damage? I used a $3.85 strap-type wrench from Tractor Supply for the filters. It works good for the engine filter since you can put a 1/2" drive socket wrench in the end. Or use a 3/4" open end on the outside. Rather than include the picture of the wrench, does the gap in the air filter cap look OK? I doubt it leaks air, but wonder if other's look like this (gap widest at arrows).