How to I fix tile that have be overgrouted!? We laid tile in our shower and I used too much grout....

We laid tile in our shower and I used too much grout. Now I obligation to know how to get the grout lines even short damaging the tile. Any sustain would be appreciated.
Anybody enjoy experience next to Sears Cabinet Refacing?...
Answers:    THEY HAVE A WONDERFUL TOOL AVAILABLE (I believe
its a Dremel product) that grinds the grout out . it's an attachment that fits on the rotary tool. I did a project some years back where on earth had to remove the grout next to a carpet pierce
and a putty knife which be the job from hell. A couple of years ago my Sis have a very expensive marble floor that she needed to save but the grout be so dirty that it was an embarassment. We used this grout removing tool and I needed to cry it was so straightforward. Once this tool gets started it wiill verbs down into the space between the tiles and will stay straight and on track.Than just regrout.