Third member date code compared to car build date?

[Carnut6870]

Hey all.  I'm collecting parts for a GT350.  The car has a Ford build date of mid March.  What would be an acceptable date code for the third member?  I have two on hand that I could use. One is dated Jan. 11 67, the other is dated Aug of 66.   Is the Jan. too close to production of the car?  The Jan. coded third member has a fill plug as does my rear end housing. The 66 third member does not have a fill plug. Would it be possible that some were built with both fill plugs?  Thanks

[J_Speegle]

Yes its not unusual for there to be two fill plugs - 3rd member and housing.

Other examples from around your cars production period at Milpitas that I have records of had 3rd member main casting dates from Dec 1966

Hope this helps

[FordGT]

My 350 built date is mid Feb of 67' and 3rd member is dates early Jan 67'  C7ZX-A 3.89 7A8

[shelbydoug]

I think 3 to 4 weeks before the build date is about right although it varies according to the time of the year. The later the build the closer they seem to get.