Here is a photo of an inexpensive Chinese pickup. I have fit new bridges on a lot of these. Usually for a 4/4 size violin you need to use a 3/4 size bridge because otherwise the "heart" of the bridge is too close to the strings.

I have seen plenty of these where the plastic mounting bracket does not match the curve of the violin's top. Since I have never tried to remove these I always thought they were glued onto the top. Recentally I needed to remove one and found out they are screwed to the top.

For the ones where I am fitting a new bridge and the mounting bracket does not match the arch of the violin's top, I am going to try to carefully remove the strip. Then protect the wire using a little bit of foil, get out my heat gun and heat the mount up a little and form it to the top. Then fit the new bridge to the slightly curved bracket.

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