  We summarize some of the results presented in arXiv:1801.07975
[nucl-th]\cite{FSIpaper}(to be published in EPJC in 2018) on modeling electron
and neutrino QE scattering on a variety of nuclei within the impulse
approximation. We find that with three parameters we can describe the final
state lepton energy for all of available electron QE data on Lithium,
Carbon+Oxygen, Aluminum, Calcium+Argon, Iron and Lead+Gold. The first
parameter, the removal energy $\epsilon^{P,N}$ is extracted from exclusive
ee$^{\prime}$p spectral function data. The second parameter $V_{eff}$, which
accounts for the interaction of final state leptons and protons with the
Coulomb potential of the nucleus, is available from published comparisons of
inclusive QE electron and positron cross section. We extract the third
parameter $U_{FSI}(\vec {q}_3^2)$, which accounts for the interaction of the
final state nucleon with the optical potential of the spectator nucleus (FSI),
by fitting all available inclusive QE cross sections on nuclear targets. Here
$q_3$ is the three momentum transfer. With these three parameters we can model
the energy of final state electrons and nucleons for all available electron QE
scattering data. At present the uncertainty in the value of the removal energy
parameters is a the largest source of systematic error in the extraction of the
neutrino oscillation parameter $\Delta{m}^2$. The use of the updated parameters
in neutrino Monte Carlo generators reduces the systematic uncertainty in the
combined removal energy (with FSI corrections) from $\pm$ 20 MeV to $\pm$ 5
MeV. In this short contribution we only summarize the results for Carbon+Oxygen
and Calcium+Argon
