Trying to get rid of four-wheel drive, is it possible to do so without removing transfer case?

The catch to this is that you will set error codes due to the missing parts as well as a multitude of other issues. There also isn't any real benefit to it as you would be changing out a lot of parts and many of the parts from a 2WD won't fit the 4WD frame as the mounting is different. In reality you would be much farther ahead to just buy a 2WD and start with that. To remove 4X4 you will need a different transmission as you don't have a tail shaft extension or the correct output shaft to use for 2WD, then you need the rear drive shaft. Next you need to remove the front axle assembly, which also mounts other parts to it. The front suspension would need to be altered because the 2WD version uses a conventional spindle and bearings while the 4WD uses a hub that the axle holds together. Then electronically you would need to devise a way to remove the 4WD sections in the ABS and engine controls. Or just ignore the 4WD or buy one that is already 2WD.
I know that isn't what you wanted to hear but unless you have a full shop and a lot of time and money, selling what you have to buy the other version would be far better.