Yes, the engine will come out with just the grill and radiator removed.
If your tranny is a 3 speed, yes it'll come straight out with the engine too.
If it's an original 4 speed it probably won't as it hangs down further than the 3 speed but I've not done a 4 speed so your use may vary...

That said, removing the front clip is fairly easy and may expose some needed repairs that you otherwise won't know about. I've done 2 different AD trucks and both needed front cross member repairs.
The entire clip comes out as a single unit and you don't have to remove the hood. Remove 7 bolts per side, 2 under the radiator, 2ea fender supports, label and disconnect the front lighting assembly at the left side screw terminals (may have to disconnect the cross over wire at the right side terminals), fasten a chain or lift belt to the forward fender support bracket bolts and it'll lift off just about perfectly balanced.
If you've got an engine lift and a concrete or asphalt floor it's a one man operation.
You'll be amazed at the ease and access it affords.
Good luck
Dave