50 Miles each way is asking A LOT from off-the-shelf lead-acid battery technology.
I don't think a BEV conversion of that Geo would be a good way to go.
Just for example. I have 800 lbs of batteries, and am expecting to be able to go 30+ miles.
Perhaps a serial hybrid would be a good idea - Convert to electric, but with a gas/diesel/E85 generator of some sort.
This is the general design of the Chevy Volt and similar vehicles.
If you haven't seen it already, check out CoyoteX's Geo Metro
Parallel Hybrid project.