Waxy, it is very different from a rwd setup, as the diff is integral with the transaxle case.
It is possible, as in anything is possible, though the stock ratio probably isn't the best. And most budget conversions do not approach 75mph. Peruse the top speeds/ranges and conversion costs over at
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But you are talking about cutting apart the transmission case, removing the bits you don't need, and coupling up an electric motor, this is pretty serious and a fairly rare bit of fabrication, which also needs to stay oil tight.
Many folks actually need to use 2nd and/or 3rd which means you need a compromise ratio for your single speed. Here is a transmission ratio chart:
Different Racing
That site also has some s-series auto to manual swap info that I found very useful:
Different Racing