OCR to text printed on a metal plate

I am working on an OCR project that aims to read a stamped serial number from a metal plate:

I am using OpenCV to prepare an image for OCR and use Tesseract for the OCR itself. This is the ideal process:

• In the image of the whole plate, crop to the common place of the serial number.
• Prepare cropped image for OCR.
• Apply OCR.

My current process:

• Configure the serial number manually.
• Convert to grayscale.
• Sharpen.
• Use Canny edge detection.
• Launch Tesseract OCR.

However, I have very limited success. My main questions:

• What processing optimizes OCR? Makes edge detection a good start?
• Can I use a bullet font to my advantage?
• Can I use the "color" of the text (as opposed to gray metal or black / white labels) to my advantage?