vintage tamiya avante 2001 and king cab upgrades

[mattf77]

I have just rediscovered my two old RC cars. want to get them running again but bewildered by all the new electrics.
can either of these handle a brushless motor and lipos or should I just get NI-Mh and a 540t motor.
if they can be upgraded do i need to change gearing and any suggestions on kit to put in them.
Many thanks.