Have you talked with your local MF dealer? Aside from that, it isn't difficult to change oil, filters and even replace a hose on a tractor. At most a 2 hour job to change all the oil and filters, might take a bit longer to replace the kinked hose depending on location but nothing that anyone with a few tools cant do. I would assume that the filters have been changed at 50 hour like all other tractors require so they should be easier to remove than the first time when the factory 800# gorilla put them on. This is a common complaint on the first filter change that they are extremely hard to remove but after that, they should be quite easy. You just need the correct size filter wrenches (may need a couple different sizes), some basic wrenches and containers large enough to hold all the oil. Follow the OEM manual for correct oils and capacities or just tell the local dealer that you are doing a 400 Hr. service and they will give you everything that you need. Remember that almost all 4 WD units have a double drain for the engine, one on each side of the drive shaft. Your OEM owners manual should have all the photos and instructions needed for even the most inept mechanical person to manage this service.
Also if the weather is not the best, it isn't going to hurt to go over the hours a bit and wait till warmer weather is available if you don't have a shop to work in.
