L1987-2003 master cylinders all seem to look the same.
So much, it's not yet known what the difference is. They all came with a 3/4“ bore.
The replacement body (one piece bore/bowl) is the same part number from L1987-2003.

Used on 1992-1997, 2000-2001 Sportsters
Bore: 3/4”
Body: Aluminum one piece construction

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Used on 1998, 2002-2003 Sportsters
Bore: 3/4“
Body: Aluminum one piece construction

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