Greetings all. I just moved to a rural area and found a 1970 duster. I am well versed on this era Charger but I am lost with anything else. The car is sitting in the weeds but not sank in the ground. The owner was outside so I stopped. He claims to be the original owner and bought it about 20 miles away from the dealer. He says the car is a 340 car and came with a 3 speed. He later changed the 3 speed for a 4 speed. The car is blue with a white vinyl top. Only rust I saw on my walk around was in the rockers at the rear of the doors on both sides. He claims it all original except one repaint of the original color and the tranny. What do I look for to verify it’s a 340 and not a 318 and is there anything else I need to look for? It’s a bench seat car and the interior is still nice. No bubbles under the vinyl top. The car looks good but I just did a quick walk around. I wanted to be courteous because the owner is elderly and I wanted to be respectful to him. Sporting Cragers and white letter tired from the 80’s. What do I look for, what are the weak spots of this car for rust, and a wild guess on value if you have one. Thanks for taking the time to read my post and thank you in advance for any replies.