I believe canadian electric vehicles (canev.com) has an adapter kit specifically for the dodge neon but I know nothing about it.
To get anywhere near 100 miles of range you are going to need a lot of battery, like probably about 25-30kwh. That will be your largest expense and the only practical way to get that much and still have a driveable car is with lithium. 144v, 200AH would probably do it, certainly it would be in the ballpark.
Your performance goals are readily achievable with a standard issue DC, 144V system. Acceleration will be modest but usable if you use a curtis controller. For better accleration you will want a Z1K or soliton or other controller in the 1000A ballpark.
It takes about 100 square feet of solar in direct sun to generate 1 kilowatt of power. It will take about 10 kilowatts of power continuously to maintain flat-and-level 55mph in a neon. Most vehicles won't see a benefit (and many would see a net loss of efficiency) from stacking a bunch of solar panels on them due the extra weight and loss of aerodynamic efficiency. The only place that solar on a normal vehicle could make sense is if the vehicle has a large, flat roof area so the panels don't affect the overall body shape much and where the vehicle sees a lot of direct sunlight. A delivery van in arizona could get a noticeable percentage (but not all) of its power from solar if set up this way for example.
Put the solar on the roof of your house and feed unused power back into the grid if your local utility supports this. That way you can optimize the angle of the panels for pickup up sun in your area and no matter how big the array is it won't affect your car's aerodynamics and it still works when your car is parked in the shade. Of course if you live in a wooded area or otherwise don't have a good site for it, you are out of luck on that front. Perhaps you can buy renewable energy credits from your local utility in that case.
There are books on how to do conversions, e.g. Bob Brandt's "build your own electric car" and Mike Brown's "Convert it" which both describe EV theory and step-by-step conversion. I prefer the brandt book. Amazon has both. If you have a local EVA chapter, I suggest going to a few meetings.
good luck.