What's likely interchangeable:
* Engine: If both have the same big block engine (e.g., a 454), parts will be largely interchangeable.
* Transmission: Manual transmission parts should be very similar, if not identical.
* Drivetrain (Transfer case, axles, differentials): These parts should be highly interchangeable.
* Suspension components (springs, shocks, etc.): Very likely interchangeable, but double-check specifics.
* Brakes: Many parts are interchangeable, but there might be some caliper or rotor differences based on specific options or GVWR.
* Chassis: While they often share the same frame, it is possible to have some variation.
What might *not* be interchangeable:
* Body panels: While some might be similar, there could be differences, especially if one truck has a different trim package or optional equipment.
* Interior parts: These are more likely to vary depending on options and trim levels.
* Electrical components: Some electrical parts may have differences depending on factory options.
Frame: The 1994 Chevy 2500 and K2500 were *not* built on a 3500 frame. The 3500 series used a heavier-duty frame. You have a 2500-series frame.
Important Note: Always double-check part numbers before purchasing. Even though parts are generally interchangeable, there can be subtle variations based on options and build dates. Using a reputable parts website that allows searching by VIN is your best bet to ensure compatibility.