lowest without compromising the ride much is a 2/3. Go with keys up front and coils with shock extenders out back. Lowest you can go is 3/5, but it won't ride like stock. I have one for sale if you want to go that low. It's a DJM.
Sorry to say this but the 3/5 that comes from McGaughy's is muck better. It won't ride like stock but the McG coil in the rear is much better than the DJM. another problem I have seen with the DJM kit is the front lower control arm will break where the torsion bar fits into it. Try the McG, but I've got them both in stock.
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