Unusual Serial Stamping on Corona built Guild

[Guilderagain]

I saw this Corona built X-150 on Ebay with this rather obnoxious looking serial number stamped/labeled on the headstock. My X-500 built in Corona has the traditional (more aesthetically pleasing) stamped serial number. When did they start this? :shock:

 

[jazzmang]

Looks like a factory second serial number. Not a pure Corona serial number, obviously.

 

[Nigel Wickwire]

Also discussed here:

http://letstalkguild.com/phpBB2/viewtopic.php?f=15&t=23734

and here, about half way down the page:

http://letstalkguild.com/phpBB2/viewtopic.php?f=10&t=23730

~nw

 

[adorshki]

Also discussed here:
http://letstalkguild.com/phpBB2/viewtopic.php?f=15&t=23734
and here, about half way down the page:
http://letstalkguild.com/phpBB2/viewtopic.php?f=10&t=23730
~nw

This started me wondering if it's even Fender doing this or could it be MIR Corp, the same folks who handled the Contemporary series? Just curious. It's definitely not a Corona "first".