A hone being a grinding stone would be used on steel/iron and the reamer is used on soft metal such as bronze which is what you would expect to see bushes made out of. Different ways to skin a cat, depending on circumstances. The gold standard is to 'line ream' , which would entail setting the steering knuckles up on a machine so the reamer goes through dead true.
You normally use an adjustable reamer with a pilot to line up the holes.............although best practice is to install, broach and ball burnish the bushes in one go ,ensuring concentricity.......Warren and Brown (Repco) at one tme made long fixed size king pin reamers in various truck pin sizes ...I have a few ,never the right one though.
I think they are both good engines, the 345 being advertised as 34HP smaller.
Depends a lot on the work needed to be done. If you want to cart your full GCW all day every day you will want the power of the 392 and just keep filling it up with fuel to get the work done. If you will only be fully loaded occasionally and you don't mind how long it takes to get wherever you are going, the 345 would be adequate, and use less fuel doing it, but noticeably less powerful.
If you plan to be loaded a lot, you will want to stick with the standard gearing, and the 392 will guzzle fuel, even empty.
If you will only ever be lightly loaded the 345 can be reasonably economical (and fast) with faster gearing. I have no experience of a 392 with faster gearing, but it would have to help on fuel, and theoretically have the extra power to pull the higher gearing.
Our 345 with 0.82 overdrive gbox and 6.5:1 diff with a 4.5t load will average 8mpg on the open road, which i consider exceptionally good. She can be (is) fast too, i don't see top gear very often in normal use.
Neighbors 392 with direct gbox and 6.83:1 diff uses a lot more fuel, even empty, but i have never tested the consumption, it just had to get the work done. The standard fuel tank wouldn't do a full/big day during harvest.
345 seem a lot more common to find nowadays, the 392 was usually in the larger models meant for harder work, they did it and got worn out doing it, then were often replaced either with a diesel like a 6v53 GM or a V8 Perkins, or often more simply a 345 because the truck was being relegated to lighter work by that stage of its life anyhow.
I do have a 345 here with a 4 barrel carby on it, but the engine was seized when i got it so i don't know how it performed in that configuration.