Don't call it a 180SX unless it's a 180SX. That's like saying you drive a Silvia. It's a 240SX.
I don't see how you think that selling a '95 Civic is going to give you enough to both buy and insure a 240SX and then pay back another $1500 worth of debt. Especially since the market for Civics is completely saturated and the market for 240SXs is the exact opposite with all the stunnaz snapping them up left and right.