I agree under the tunnel after the box is stealth and simpler
Netgain had this idea and pattented their system way back
in 2006 and there have been heaps of copy cat companies
since using the same concept which Netgain coined EMIS
http://www.go-ev.com/p20070301_EMIS_Release.html


Interestingly there are 2 opposite concepts by GM in which
they have 2 different systems themselves and the first one
is using an electric motor/alternator which is like my first
vid of the Sema concept.
https://www.youtube.com/watch?v=X_4d9o8E8z4

Its a much smaller e motor running off the crank snout
for take offs and regen. Datto cranks are forged steel
but their snouts are not made for electric motor torque.


The second concept is very interesting and similar to toyota.
Its on an inline box but no gears? just 2 electric motors acting as
the drive/regen and variable speed gearing for the gas engine.
Well thats what I understood could be wrong but great idea.

While this unique fella is like you were thinking Matt but
only for freeway speeds very clever concept again.
I recommend everyone watch this its so well thought of
for those who want big trucks with economy and still be
able to power through with their gas engines for fun.
https://www.youtube.com/watch?v=TLPR2-7-xpM

This small 30lbs motor the size of a large alternator
is a great upgrade and possible no probs for the forged
A series crank snout.
30Kw peak, 60lbs of torque and only 35lbs or 16kg in weight
http://www.evdrives.com/product_p/mot-me1115.htm