If you want to keep the straight axle and soften the ride up, best thing I can suggest is talk to a spring shop. You can get the monoleaf front springs, but if you don't want the 3" lowered height they are designed for, have the spring shop recurve them for that 3" height back. Should be cheap and easy to do.
I am thinking of that myself. I have a rock-hard 3/4 ton, but keeping the straight axle wouldn't bother me so much if I can change two things, the harsh ride and the stock steering. Fix those two things and my complaints about my truck are over.
I mean, look what all the street rodders do. There are different options that still allow you to keep the straight front axle. I suggest looking into Speedway Motors for some options.
Fiberglass Vette springs are a dang good idea, actually. Glad you mentioned it. I have a 330 lb/in fiberglass rear spring in my Corvette and it rights VERY well for a leaf spring car. Also handles very well. Now that you mention it, I bet I could think of a way to convert my truck to a transverse Corvette fiberglass spring. Or even two Vette springs in the stock locations, if they're very light springs. Thanks for the idea.
