Considering 70 Duster

In my opinion if it looks good to you and runs strong, take a look at the rear shackle mounts, the torsion bar mounts and the floor. If they are all solid $5500 sounds like a lot of fun for the money. A 340 car would start VS and have an H for the 5th letter. C means it started life as a 6 but that doesn't matter at that price point. You might want to look at the rear end to see if it has a backing plate or not. If no backing plate (removeable carrier bolts holding the front on the differential) 8 3/4 rear is a huge plus.