The oil/grease debate can get heated.
If you look at the trunnion, you will see a slot cut in the threads. This is to allow oil to easily flow to all the threads. It has the unfortunate effect of allowing grease to bypass the threads and quickly exit the trunnion. This means injected grease does not force the old grease out but simply quickly exits and the old grease remains.
I use an dedicated oil can with a pump to squirt oil into trunnions. Very easy to do.
All the parts you need are listed in the parts manual. It's a good reference to make sure you are not missing anything.
One point of note, the front wheel bearings do not use a seal. They use a grease impregnated felt ring. KEEP THE OLD FELT RINGS. New felt rings are way too thick and do not allow the bearings to seat properly. THIS IS DANGEROUS. Reuse your old felts. If you threw them away, you have to trim down the felts to the correct thickness. Mount the hub and tighten the adjusting nut without the felt in place. Note where the nut is. Make sure that the nut goes to the same position when the felt is in place. When the felt is the correct size, the bearings tighten up at an exact spot. If the felt is too big, the bearing tighten up in a weird, soft sort of way with no distinct exact point of tightening.