* Engine Mounts: The engine mounts on the S10 pickup and the Blazer are different. The engine won't physically bolt into the Blazer's engine bay. You'd need custom mounts fabricated.
* Wiring Harness: The wiring harnesses are different. You'd need to either extensively modify the S10 harness to work with the Blazer's system, or rewire much of the Blazer's system to accommodate the S10 engine.
* Computer/ECU: The engine control unit (ECU) is incompatible. You'll need to find a way to get the correct ECU for the engine and get it to communicate with the Blazer's sensors and other systems. This often involves tuning and potentially a standalone engine management system.
* Transmission: While some transmissions might be interchangeable, it's not guaranteed. You might need to swap the transmission as well, adding to the complexity.
* Exhaust System: The exhaust system will need significant modification or replacement to fit the new engine.
In short, while it *might* be *possible* with significant mechanical skill, fabrication, and electrical expertise, it's a very complex and time-consuming undertaking that is far from a simple bolt-on swap. It's generally much easier and more cost-effective to find a compatible engine and transmission for the 1997 Blazer.
