R60 motherboard replacement question

[roymoore]

I have 2 R60's I'm replacing the motherboards on. I want to be very careful with the Unit S/N # so the XP product #'s will work. When I boot the maintenance disk on another R60 it shows a motherboard S/N that looks similar to the replacement motherboards, however the Unit # is different. The unit # is 1S946152ULVAG938. I get the 946152U is the type and LVAG938 is the S/N #. What is the 1S in the beginning? Should I follow this pattern when I update the S/N on the new eeprom?
Thanks for any advice

[RealBlackStuff]

Your Maintenance disk shows an example of how the key is built up.
The "1S" at the beginning is a fixed part of every key of that type (20).
1S TYPE Model Serial
1S 9461 52U LVAG938 (without spaces) = 1S946152ULVAG938
You need to delete the old 20-key before you enter the new one.