440 vs 383 exhaust question

[70 sublime]

A while back I was looking for a 440 to build up
One of those right time right place kind of thing so I bought one
I now have a block back from machine shop but not sure what to do with it

The 70 Charger project car I want to put it in will take me a couple years to get it ready for a motor ( I hope only a couple years but you know how things go sometimes )

Do I store it all apart till I have the car ready then put it together or just build it now

If I build it now I might be tempted to pull the 383 out of my 69 Charger and put the 440 in and tinker with it in a car

So this is all leading up to my question and how I got here

The 383 has a set of the HP cast exhaust manifolds on it and if I were to swap them onto the 440
How much space will there be from the end of my 383 exhaust pipe I have in the car now to where the 440 exhaust manifold would end up ?

I was looking under my car the other day thinking about this
I got my dual exhaust built at a muffler shop and the pipe from the manifold to the cross over all the way back to the mufflers are all welded together in one piece

I know the 440 will be higher off the ground and wider apart than the 383 so would there be such a thing as a spacer to fill this difference or would I need an all new pipe from motor to muffler ?

Love the 383 I have in my car now so it will be going back in no matter what as it is just enough zip to have fun but not get into too much trouble
In the end I am going to end up with two cars and the one with the 440 will be the one to go waste some gas with when I feel like just a little more zip is good

[XH29N0G]

I put one size headers on a 383 and they hung down a little lower than I would like, but not a lot.  Now that I do the math, it works out to something like  the 440 will be 1/2" taller and 1" wider, I wonder if my headers were just a little on the cheap side. 

My estimates assume a 90 degree V and are calculated from the deck heights of 9.88 and 10.73.  This would move your pipes out and up by 1/2 inch in each direction.  I do not know how this would affect the way they meet the block.