Will a Chevy 350 engine mount to a 42RLE transmission?

No, a Chevy 350 engine will not directly mount to a 42RLE transmission, as they are designed for different manufacturers. The Chevy 350 is a small-block V8 engine, while the 42RLE is an automatic transmission typically used in Chrysler vehicles. To connect them, you would need an adapter plate or custom modifications, which can be complex and may not be practical for most applications.