[Elecraft] 10Mhz sig source for 2m terest/eme...specific question

[Randy Lake]

Good evening all. After seeing all the posts on GPSDO's I need a bit of
advice and clarification.
I have a K3 with new Synth boards (main and sub). I am thinking I need
equipment for freq stabilization/reference. I am looking at all of the
following and am not sure if I actually need all or any, and if I should,
do I need all of the following:
Will be using -  *K144XV
<http://www.elecraft.com/manual/K144XV%20Data%20Sheet%20rev%204sm.pdf>
Internal
2 M 10w Option*
*KTCXO3-1  TCXO*
*K3EXREF*  *Ext. Frequency Reference Input*
*K144RFLK  K144XV Reference Lock Board *
Leo Bodnar GPS Frequency Reference (or something similar)
Any guidance will be greatly appreciated!
-- 
Randy Lake N1KWF
73 Gunn Rd.
Keene,NH