Slant 6 to 318 swap, 72 Duster, Using 75 D100

So im looking at a 340 duster that has bad rust in the floor panel witch the entire drivers and pass will need new sheet metal. the engine is all there but it is spread in parts in the cab of the car. If he will take 2k im looking at getting it and this would make the job easier, I could do a complete swap pretty easily if i am not wrong. Just seeing what everyone’s input is on the subject. ill atach pics of the 340 let me know if this is a bad price.