Can I use electrical tape to just tape the ballast to the fixture if I've lost the screw to hold it in place?


Not a good idea at all: ballasts get pretty warm and eventually (probably sooner than later) the tape is going to release the ballast and let it fall. Use a screw, either one identical to the first one or a small self-tapping screw that will make its own hole in the fixture housing.

Updated on January 15, 2018

Original Article:

How to Replace a Fluorescent Ballast
By Dan Harmon