From all of my experiances with the Aldans, I must have changed them out 8 times at least, I would say about three hours to do all four, not counting placement for the external resevour. Since you won't have to reuse the oem fork in the rear, this will make things a bit easier. You will have to remove the upper control arm to remove the oem fork in the rear, but this is very simple. The fronts are fairly simple to change out. I don't think resivoir placement is a problem with the SRT. Seems like the SRT's I've seen found a couple conveniant places to mount them.
You asked how low should you lower the car, I would not go more than one full inch. I've heard it from several suspension experts, and they all say not to lower the car more than an inch. You start running into problems, such as stiction, binding, geometry issues, and not to mention dragging the underside over certain obstacles. One inch really shows up as a nice drop. I'm not yet an expert in this, but I think it's best not to go to fare with this. I'm supposed to be working on this my self, and will be working with some really good suspension experts very soon. I hope to learn much.
You will have to do a four wheel alignment, and what ever you do, have a very competent tech do the alignment, and tell them you are going to want a print out before they even start. I would also deveate from the oem alignment specs a bit, as they can be improved on.
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