So for us wanting to try oil cup with existing FogMod units, it would be advised to get as much of the aeroshell grease out of the unit before switching to oil?
Chase, here are some tips for you and others I've done the mod for.
Below is a repost of the required parts to modify the FogMod I've done based on the 1/4-28 grease fitting thread design. If you haven't used a 1/4-28 thread, adjust the adapter to fit your thread pattern.
Do your best to get out the Aeroshell. If there is some Aeroshell in the reservoir I don't think there will be a big issue. Some degreaser should work fine. There is a possibility that the grease can block the hole in the bushing so you want to make some effort to remove it. Aeroshell is very good grease so if it mixes with the oil I don't think there will be a problem.
There may be some minor modification necessary to the adapter and coupling. For the most part I tried to center the grease fitting to the area provided so it may be tight to get the adapter and coupling to fit. I had to modify mine and I would expect most if not all the previous FogMod's to require the same filing. The McMaster parts are aluminum so they will file easily. It may also be easier to file under the target wheel housing instead. So you will need a file (there is a chance you won't, but unlikely).
*From here on, placement for FogMod's with the grease fitting will be a little lower so you don't have to worry about it.
I had to add a small washer as a spacer between the adapter and the threads. The adapter gets a little tight will a 1/16 space so I filled that with a tiny washer.
All said some minor (IMO) work is required. For those of you comfortable with greasing 1-2 a year with only a small amount I don't think there is a reason to change if the work described above to too difficult. People have different levels of expertise and comfort and I understand that. That said if you are savvy enough to pull it and install it the work should not be difficult. Two important things to remember.
1. Be careful with aluminum thread. Tight, but not too tight. If you think it's tight enough it probably is!
2. Degreaser may remove sharpie marks so be careful. Put the lid on before spraying and watch you LDI label. Those numbers can rub off.
I got the parts from McMaster Carr. The below images are for those with a 1/4-28 FogMOD'ed fitting.
Low-pressure Aluminum Threaded Pipe Fitting, 1/8" Pipe Size, Coupling, 15/16"l (.93"), 19/32"od
Threaded Elbow-style Oil-hole Cover, 1/8"-27 Npt Thread, 1/4" L Thread, 25/32" H O'all
Grease Fitting Adapter, Stl, Straight, 1/4"-28 Taper Male X 1/8" Nptf Fem
Standard-wall Aluminum Threaded Pipe Nipple, 1/8" Pipe Sz, Fully Threaded, 3/4" Length, Sch 40
The below images show fitment. They are not tightened.