How do I lift out a drop-in oven? I need to pull out my electric range
so I can see if there's a gas outlet behind it before I buy a replacement.

Also, how do I put the oven back? By removing it, will I have thrown
anything out of whack that needs adjusting or replacing?

Never knew these existed !

Here's a link to someone with the same issue:

http://www.diyprojects.info/bb/ptopic9858.html

If i were to attempt it I would; remove the oven door (pretty simple
really only a couple of screws on some, none on others, if there are
screws remove them, catch it on she slightly open catch and lift up)
remove the shelves, (now you've removed a considerable portion of the
weight), pick it up by reaching into the oven compartment, have a
friend help with balance.

Eric in North TX wrote:
If i were to attempt it I would; remove the oven door (pretty simple
really only a couple of screws on some, none on others, if there are
screws remove them, catch it on she slightly open catch and lift up)
remove the shelves, (now you've removed a considerable portion of the
weight), pick it up by reaching into the oven compartment, have a
friend help with balance.

Even without the door, it's that light?