No, a 1993 Mark VIII 4.6L engine and transmission will not fit directly into a 1995 Ford Thunderbird without significant modifications. While both are Ford products and use similar-sized engines, the subframes, engine mounts, and other supporting components are different enough to make it a very difficult and likely impractical swap. The transmission bellhousing patterns are also different.
While some parts *might* be interchangeable, a direct bolt-in is not feasible. You'd be looking at extensive fabrication and custom work, far beyond a typical engine swap.
