Both Galewitz and Gilevich are representations of a Russian or Polish name
in English letters. -vich and -witz both represent the patronymic ending.
The vowel variation is common. You know what the name sounded like, and
both spellings are attempts at that sound.
One of the first rules of genealogy is that spelling doesn't count. You
have to consider any possible mangling of the name when you look at
records. Especially when translating >from one language to another, and
especially with clerks who wrote down whatever they thought was good,
there will be big variations in spelling. My Mincho ancestor was written
as Minckle in one record, so just consider what the sound might be similar
So, in brief, yes, Gilevich and Gallewitz could be the same name.