What makes you say that? Other than having a non-OD shift needle, looks like the same instrument cluster as my 1984 300 had stock (no tach, 0-85mph speedometer). The only diesel-specific things I know of are different tach options, a slower speedometer (mainly on medium duties), and possibly a glow plug light (which would have been a swap for the shift light, if memory serves).
1984 F150: 300 L6, AOD, RWD. EEC IV / TFI, Feedback Carter YFA Carb. Stock everything but radio (for now).