I switched from a 230 to a 292 about a year ago on my 63 chevy pickup. If you are buying a complete motor and not a long block the only things you'll have to worry about is the radiator being big enough, the exhaust manifolds being about 2" higher, and that passenger side bracket. I luckally got the brackets when I bought my engine but If you don't have it you'll have to hunt, there is a difference in the shape. Lucky for you your truck was made to work with this engine, if you look at your engine crossmember you should see two holes drilled a few inches in front of the passeger side mount (thats how it was on the 63 at least), you move the new mount up to there.
If your buying a longblock however there are a few things that won't mix namely the water pump and side cover. A stock intake will work from the 250 but you'll wan't a bigger carb (though the 230's one has worked for me in a pinch), I think the fuel pump is the same, the oil pan is bigger, altenator brackets might be different depending on the water pumps length and all that I'm not sure, the valve cover is the same and so is the distributor and coil.
Is there anything else? Good luck on your project, You'll love the 292s extra grunt. K.
