All kinds of Lotus emblems can be found on ebay. Many are smaller than that 3" you are looking for . Maybe with a bit of searching.....
Or.... Glue a plain disk over the Mazda Logo and then put a smaller Lotus Logo centered on the disk.
Or.... find someone with a lathe to turn the Mazda logo flat, eliminating the logo.
OR just fill the Mazda with bondo and repaint.
Plenty of ways to accomplish what you are after.
_________________
Chuck.
“Any suspension will work if you don’t let it.” - Colin Chapman
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