Suspension advice

I have a 69 Dart thats in major need of some suspension upgrades. The car was originally a 6 cylinder. Now its a procharged 318. I did put disc brakes on it about 10 years ago. But they are still manual brakes. I has a warn out manual steering box. It has the original 6 cylinder torsion bars and all the original bushings under the car. It has super stock springs in the rear. ,that who knows how old they are. I have the car currently lowered in the front(torsion bar lowered) and lowering blocks in the back. I dont want to spend a crazy amount of money, so I dont want anything completely radical. I just want it to be lowered the correct way and be able to handle really well. I want to take it on a long trip this summer.

Any suggestions would be great! Thanks guys!