help with a serial number please!

[greenfeverms]

i have got an old jd 520lp, the serial number is 5200013. all i can find out is serial #520017 was used in the nebraska test #390 and serial #s start at 5200000. also found info stating that 5200017 was the 1st lp built, so this is confusing........ any help would b appreciated!

 

[CLW]

I can make your day worse. My "John Deere Tractor Data Book" by Lorry Dunning says 5200999 was the first 520LPG built and shipped to Dallas Texas. It says that 5200000-5200018 were shipped to the Engineering Dept. May 4, 1956. I know sometimes these tractors are kept in testing for X amount of time and either scrapped or sold as used. I know this don't help any but it's all I got.

 

[greenfeverms]

thanks CLW it does help. this seems 2 be a unique tractor just not sure just how unique it is yet. any more info would b helpful.