magnum accessories

I was wondering about the advantages and disadvantages of converting the magnum accessories, (ps, ac, alt. ) to LA style accessories.
What I am working on is not a a-body. Its a 87 Dakota. But I ask on this forum because it seems there is a lot of knowledge here that would apply to my swap. So thanks for helping me!!
I have seen the hughes snout adapter for the cam, and Im thinking with this, I could use my 3.9 liter accessories off of my truck now. This would allow me to go back to a mech. fuel pump and I think the placement of the accessories would fit under the hood better.
Now length of the motor is a problem. I have to eliminate the mech. fan and sandwich dual electric fans between the condenser and radiator. That is what the factory did in 89 with the Shelby Dakota, in order to make room for the v8. That being said, does anyone know if converting the maganum to LA accessories makes it any longer or shorter?
I plan to run the edelbrock intake with a 670 street advenger carb. (the carb I already have) and probably a standard mopar electronic ignition.
Is it as simple as getting the snout adapter and the 87 accessories bolt up to a magnum engine?
Am I missing something here?
Any input on this project would be appreciated.