you will need the X fillers (for 400 & A/C cars) , very likely not on the car unless it was an A/C car(Ames FP 191 $99), the masticted lower fillers (Ames FP454, $14) also called "seal kit"(rubber fillers), and lower valance panel (Ames FP191L , but its fiberglass and for 67,68, you probably need a 69? and should try finding a used metal)

that should get you what a 400 had and 350 didnt....

I think the rest might fit...and if you have a 71 , shouldnt you have it complete?

mine is a 72 400 and came complete with a different PS pump, bracketry etc , but the X fillers and one of the rubber fillers were missing...changed 15F after I installed those..it HAD the lower panel for some reason. my car WAS a 350 non A/C car