Sharing my experience. 1994 F350 460 7.5 Had ongoing oil leak at base of engine oil dipstick tube see picture. Job was much easier than I thought it would be. Not knowing how it goes together figured would be riddled with problems. Went good, one nut has to come off the exhaust manifold holding the dipstick tube on. When nut came off the tube pulled out easy with light tug. The seal (o-ring) was half gone and much smaller thickness than the replacement. See picture just slipped it onto the tube into the slot. Pushed back into the pan hole and put the nut back on. The nut pushes the tube firm to the pan. The hole in the pan didn't really even have resistance other than a light push. 2 days later no sign of leak yet. Took 30 min with a 14mm socket nothing else. Parked so passenger side was a little lower than driver so didnt leak much oil. It was a little low when I started.

Also, see picture for the part number from Ford if you need to replace it. Only $0.89 where I'm at. Dipstick is $94 from Ford. DO NOT!! bend the tube or bracket it wont seal.