Your drain plug is the worst I have seen for a X in the SE.
To check temp just use a IR temp gun which will give you an exact value. To be honest once you have it full with engine running check it quick because it will go past 130 F pretty fast. Also note the low torque values for the bolts for the pan. I use an inch pound torque wrench for this application. All straight forward and the hose is plenty long.
Now more important is your transfer case. You best drain and refill that with BMW fluid because it only holds 0.6 L which is what your front diff holds. I would do the diffs front and rear as well as the transfer case because they are much more susceptable to wearing out given the low fluid values and heat...