Help needed with sb 318

Owner and I only talked briefly......so didn't get a chance to pop the hood.What this is is a truck parked on the side of the road, with a couple similar trucks and old farm equipment. Have driven by it for years, but wasn't looking for a D600, so never paid it any mind. Seller doesn't have it for sale, but would sell it.

If it's a 361, should be similar to engine in this truck.......which is different configuration than the 318 I am using now.

1974 Dodge D600 Grain Truck

Would not be interested if this isn't an easy replacement for the 318, with few if any mods to make it work. Would think it should be as it was an upgrade option for the same truck.

One more thing I found out by running the monster is the use / abuse makes it a poor candidate for an engine that runs hot. At the barn when unloading, has to run at a fast idle for 30 to 45 min at a time. Heard of one guy that tried to replace 318 with a GM big block 454.......and it always ran too hot to work.