Will a big block Chevy engine fit where 6.2 liter diesel was standard?

It's highly unlikely a big-block Chevy engine will fit where a 6.2L Duramax diesel was standard equipment without significant modifications. The big-block Chevy (typically referring to the 454 cubic inch and larger engines) is considerably larger and wider than the 6.2L Duramax. Even if the length might work, the width and height would likely interfere with the firewall, frame rails, and other components.

You'd be looking at extensive fabrication work, potentially including:

* Modifying or replacing the engine mounts: Completely different mounts would be needed.

* Modifying or replacing the firewall: The big-block's bulk might require cutting and reshaping the firewall.

* Modifying or replacing the radiator support: The engine's size and position could necessitate changes to the radiator and support structure.

* Custom exhaust system: The exhaust routing will need to be completely redone.

* Adjusting or replacing other components: Things like steering components, power steering lines, wiring harnesses, etc., might need to be modified or relocated to accommodate the larger engine.

In short, while theoretically possible with a massive amount of custom fabrication, it's not a simple swap and would likely be a very costly and time-consuming project. It's far more practical to consider a smaller-block Chevy or LS-series engine for a swap if you want to stay within the General Motors family.