Yes, I believe you’ll need to move your mounts with this swap.Boy the 4.6L didn't last long. Good luck on the 351W. Is the engine ready to run or does it need a rebuild? If a rebuild is in order, consider a stroker upgrade as it 363, 393, 408.
In moving from the 4.6L, I believe the modular engine mounts are different from the SBFs.
And possibly a different driveshaft length