Well, we have another log on the fire. Didn't know we were dealing with Muti-Power also. At this point, I would continue to pull the lift cover after you drain ALL the fluids. There are two plugs to pull. One under the cavity we are working with and one rearward toward axle. If you have an Arco dealer (Massey) purchase Permatran-3 fluid. This works well for this application and is what I have used on my 150 complete rebuild.
There are two pumps under all that oil. One for the lift pump and the other for the Muti-power. Also two filters, one for each pump. Mine were damn near completely plugged at rebuild. I've found one picture, and will try to post. Have more, just need to find them. In the picture, IPTO pump is the same as the Muti-power pump.
Might be time to ask David "from Wales" to jump into the question. He's the Man.