a/c expansion valve direction?

When mounting a/c h-block/expansion valve, does the large female fitting go up or down? I know on the evaporator side both sizes are same , but on the engine side I believe the large fitting is up?  This large size goes back to compressor so I need to get this right. :huh:

I just put a new one on my car so I know it goes up. I had a hard time connecting it back on the connections that come thru the firewall. I tried everything I could think of, but I couldn’t get them both to go in the new expansion valve. Then I tried some of the same, but just different o rings. Went right on. I spent hours and hours of messing with the damn thing. So if you have any problems with those connections, try some different o rings.

Here is pic on car. Be sure and hold the block with a big wrench to tighten the lines. I put a small amount of never seize on the threads to keep them from locking up in future but do not get on o-rings or inside.

Thanks,guys for a quick response! And happy new year!!