putting a 440 in my 69 340 dart

Just wondering exactly what I'll need to put a 440 in my dart. My dart had a 340 in with a 4 speed. I have a really strong 440 that I just had built for my 69 charger but it will be a year or so before the charger body is completely done and my dart body is ready to go. What exactly will I need to do the conversion.
-440 engine harness( i have a slant 6 one and I've heard there the same?)
-schumacher 340 to 440 mounts $150.00
-torsion bars (what size?)
-headers (not sure what to go with for least modifcation) Tri y headers $500, just not sure if they work with 4 speeds?
-I have bell house for my 440 will it work with my 340 4 speed tranny, or will I have to find a different one
-sub frame connectors

If any one can add to my list that would be great, thanks Ryan