KLAKEBRONCO
Adventurer
Yes - clocking moves the fill plug. You need to draw a level line across the back of the T-case at the height of the fill plug stock, then draw another level line once you have clocked it. Think about what your new (clocked) fluid level might leave un-lubricated vs. the original fill line, and figure out how much you need to fill now that it's clocked. You may need to fill through a different bolt on the T-case, or through the breather tube. If there is a convenient bolt at around the right height on the case, then you have a good place to fill and to check fluid level. If not, you can make a "sight glass" by putting some 90-degree fittings in a higher bolt and in a lower bolt and attaching a piece of clear tubing between them. Then you can fill from a higher bolt, and see your fill level in this tube.
To answer the earlier question mine is a 1356 T-case. So it uses ATF also.
Those are good tips to maintain a way to keep it full.
Other than the appropriate level I don't think there would be any problem at all in clocking the case. With the lower viscosity oil (vs the cases using gear oil) there should be no problems keeping everything well lubed.
FWIW I haven't clocked the stock case yet on my Bronco.