I just finished up my roof top motor relocation this weekend as well, I utilized the Ford Mustang motor/pump assembly too.
I'm attaching pictures of the pump assembly I used in case it helps other people out. I received the assembly with some of the wiring attached, including a disconnect so I reused that as well.
Some basic info on the pump I used:
- Purchased for $180 off ebay.
- It was listed being for 2008-2014 Ford Mustang.
- Made by Hoerbiger (same as the Z4).
- Pump assembly showed part numbers S109024 and HB80069-002P.
- Electric motor shows part numbers 3M5042, 1090069, and HB80006-019C.
- For wiring, Mustang red to BMW green/grey and Mustang yellow to BMW blue/grey.
- The banjo bolts on the mustang pump are the same size as the BMW, however the inlet/outlets are on the opposite side. Meaning the holes in the bolts are on the bottom when screwed in instead of the top. I'm not sure if this matters but I reused the BMW bolts just in case.
- The pump outlets were labeled 11/13 on one and 12/14. This runs backwards from BMW's setup! I initially plumbed it per the numbering on the pump and it ran in reverse, the open button closed and vice versa. So I had to switch the hydraulic lines so the 11/13 were attached to the pump at 12/14 position, and the bmw lines 12/14 were at the 11/13 position on the pump. Once done, it runs correctly.
I also did not notch the plastic, but used a 1.5" circular saw drill bit to drill a hole in the plastic to the left of the storage shelf, there's a picture below showing the location I put it in. Then the wires and hydraulic lines were easy to run and I zip tied the pump to the grounding spot on the left side of the trunk. Be sure the hydraulic lines are on the top as I'm fairly certain the pump pickup for the hydraulic fluid is on the opposite side.