Oxnard Factory Serial Number

[GGJaguar]

Not at all if you simply add a 5th digit when it's past the 9,999.

That would be the easiest solution (G&L did it). But with Guild, anything can happen.

 

[fronobulax]

Not at all if you simply add a 5th digit when it's past the 9,999.
Ralf

So I should have added without changing the format.

Perhaps I bring too much non-guitar experience to bear but there are definitely situations when the serial number cannot be changed and doing so has a cost. So the intelligent solution is to think things through before deciding on the format.