  Predicting the effects of a coronal mass ejection (CME) impact requires
knowing if impact will occur, which part of the CME impacts, and its magnetic
properties. We explore the relation between CME deflections and rotations,
which change the position and orientation of a CME, and the resulting magnetic
profiles at 1 AU. For 45 STEREO-era, Earth-impacting CMEs, we determine the
solar source of each CME, reconstruct its coronal position and orientation, and
perform a ForeCAT (Kay et al. 2015a) simulation of the coronal deflection and
rotation. From the reconstructed and modeled CME deflections and rotations we
determine the solar cycle variation and correlations with CME properties. We
assume no evolution between the outer corona and 1 AU and use the ForeCAT
results to drive the FIDO in situ magnetic field model (Kay et al. 2017a),
allowing for comparisons with ACE and Wind observations. We do not attempt to
reproduce the arrival time. On average FIDO reproduces the in situ magnetic
field for each vector component with an error equivalent to 35% of the average
total magnetic field strength when the total modeled magnetic field is scaled
to match the average observed value. Random walk best fits distinguish between
ForeCAT's ability to determine FIDO's input parameters and the limitations of
the simple flux rope model. These best fits reduce the average error to 30%.
The FIDO results are sensitive to changes of order a degree in the CME
latitude, longitude, and tilt, suggesting that accurate space weather
predictions require accurate measurements of a CME's position and orientation.
