Insurance and swaps.

I don't live in California, thank god, and where I live in Colorado there are no emissions anymore.
My question is, if I swap a hemi 5.7 into my dart.
How do I get insurance to cover it? Say I have $5000 tied up in that hemi, I don't want to have to eat it if I wreck, insurance will want to replace the 318 or s6, but not a hemi....

Also, say I move to California. How can I drive my dart? What about emissions?
Obviously the worst running hemi is gonna beat a 71 s6 on emissions.
But will the swap even be allowed? Or do u have to reclassify the car or something?

Thoughts and opinions?