Anyone here put a 354 in a Dart?

The 354 block is very close in all dimensions to an LA.
Motor mount ears, and trans bolt pattern are the same (spacer is needed because of longer crank flange on the Hemi)
Exhaust is actually easier for the Hemi than for either BB or SB Wedge, because the Hemi has downward facing exhaust ports.
Swap would be much easier than you think