New truck suspension questions

So I just traded my 01 base for an 11 SR5. The previous owner told me he towed a heavy trailer sometimes so he had the rear springs beefed up. To level the truck he had a spacer lift installed on the front. I'm ok with the lift but as seems to be common knowledge here the ride is bad. I'm trying to decide weither to take everything back to stock or what. I do haul firewood so the extra spring in the back (it has one more leaf than stock) wouldn't be bad. Keeping the lift isn't a big priority but I'm not sold on getting rid of it either. What about going to 5100s instead of the spacer? Other options? I'm pretty DIY so that has some influence.

The spacer is about 1.5". Any driveline issues at these levels?

 

First off what rear leaf setup do you have?

 

There are five leafs total, one of which is a short helper spring. Four full length.
I'll post a picture later today.

 

I would get 5100's keep it leveled but the question is how good are the springs now with the spacers on them.

 

After some research another question. It appears the 5100s just have an adjustable spring perch. How is this different than a spacer lift?

 

It preloads your spring to yield a lift but depending on your spacers that goes on top or between the spring.