Here's what the Kadee brackets get you for spacing with an 805 or 740 coupler....
I wanted closer so I modified the bracket and drilled new holes further back and shaved down the draft gear to clear the trucks.
This is how close mine are now. The couplers do a bit of slack so there is room to stretch out just a bit for the curves.
WARNING: do NOT try this on 054 or smaller curves.