There are two ways to do that:
The easy way would be to use
SADXTweaker's Object List Editor, find the object you want to port and click copy, which will put something like this on the clipboard (from the ring in EC):
arg1=2
arg2=3
disttype=1
distance=360000
objaddr=50370
textaddr=3E7F84
Now find an object you don't need in the level (you can move and expand the list, but that's a different topic and more complex) and click paste. The info in the boxes should change to the info you copied.
However, most objects need specific textures loaded, or the game will crash when it tries to load the object, or display the wrong textures. For that, you'll want to do pretty much the same thing with the Object Texture List editor. An incomplete list of texture files and what uses them is
here.
The hard way would be to do it all in hex using the info
here.