This is the listing for grilles as shown in the Ford Truck Master Parts Catalog (MPC) Jan. 1975 Final Edition:

Fig. 01 - Ford Truck Master Parts Catalog (MPC) Jan. 1975 Final Edition

All body items (including soft trim) which were previously offered for service and no longer appear in the Dealer's Price List or in an O.S.I. catalog are obsolete and not replaced.  Items which are obsolete and replaced are published in the O.S.I. catalog when stock of the replaced part is depleted.

Here is a listing of the O.S.I. catalogs I used for this research project:

• January 1980 Vol. 4 (covers Jan. 1, 1967 thru Dec. 31, 1979)
  C7TZ-B, C8TZ-E and C9TZ-A not listed
• July 1981 Vol. 5 (covers Jan. 1, 1980 thru Dec. 31, 1980)
  C7TZ-B and C7TZ-C shown as being Obsolete and not replaced
  C8TZ-E shown as follows:

Fig. 02 - O.S.I. FPS 7632-5, Vol. 5 dated July. 1981

So sometime in 1980, C9TZ-A ('69 bright grille) replaced C8TZ-E ('68 bright grille) and became a regular service replacement.
 

C8TZ-E and C9TZ-A are then shown in the Jan. 1995 O.S.I. catalog (which covers July 1, 1980 thru June 30, 1993) as follows:

Fig. 03 - O.S.I. FPS 7632-5, Vol. 5 dated Jan. 1995

Fig. 04 - O.S.I. FPS 7632-5, Vol. 5 dated Jan. 1995

Fig. 05 - O.S.I. FPS 7632-5, Vol. 5 dated Jan. 1989

An ampersand (&) following a part number in the "Disposition" column is a symbol for the word "and" which signifies that more than one part number is required to replace the original part number.

Basic 13200 is 'Parking Lamp Assy.'
Basic 13064 is 'Headlamp Door'
Basic 13118 is 'Headlamp Adjusting Ring Assy.'
Basic 13015 is 'Headlamp Bulb Retaining Ring'
 

This shows that sometime between July 1, 1980 and June 30, 1993, both the '68 and '69 bright grilles were  replaced by D0TZ-D (the '70 grille shell) as a standard service replacement. D0TZ-D was then replaced by D0TZ-E, which was then replaced with D0TZ-B, which became the standard service replacement for the '68 thru '70 grilles.

D0TZ-B is not shown in the 2001 Ford Parts & Accessories Price List, though D0TZ-E is still listed at $328.29. There is no listing for this PN in the 2004 Price List.

The 1975 Final Edition MPC (Fig. 01) shows that the D1TZ-A ('71 grille shell) was replaced with the D2TZ-A ('72 grille shell) as a service replacement by 1979.

The Ford O.S.I. catalog FPS 7632-5 (P14048) dated January 1989 shows D2TZ-A replaced with D2TZ-B as the standard service replacement for '71-'72 grille shells.

Fig. 06 - O.S.I. FPS 7632-5, Vol. 5 dated Jan. 1989

The 2001 Ford Parts & Accessories Price List still shows D2TZ-B listed at $288.21. There is no listing for this PN in the 2004 Price List.