* Engine Mounts: While the engine block may be similar, the Vortec engine might have slightly different mounting points. You'll likely need to use the engine mounts from a 1996 truck or fabricate custom mounts.
* Computer and Wiring Harness: The Vortec engine uses a different computer system and wiring harness than the non-Vortec engine. You'll need the complete wiring harness, computer (PCM), and related sensors from a 1996 truck, and possibly a custom harness to adapt to your 1994 truck's existing wiring. This is often the most complex and potentially expensive part of the swap.
* Exhaust Manifolds/Headers: The exhaust manifolds or headers from the 1996 truck may or may not fit the 1994 truck's frame and exhaust system. You might need to modify or replace them.
* Throttle Body and Accessories: The throttle body and other accessories (alternator, power steering pump, etc.) might require adaptation or replacement, depending on the specific configurations of the engines and their mounts.
* Transmission: Ensure your transmission is compatible with the 1996 Vortec 305. While a 700R4 or TH400 from the 1994 truck might work, some minor adjustments may be necessary.
In short, while the swap is *possible*, it's not a straightforward task. It requires mechanical expertise, access to the correct parts (especially the wiring harness and computer), and likely some fabrication work. Unless you have significant experience with engine swaps, it's best to seek the help of a professional mechanic.
