yes another lowering ?

[1fast71]

so i was lookin at our trucks on cardomain and i found this long bed what cought my eye was the drop it looks really nice for a long bed so he said its about a 4/6 drop? does that mean 4in in the front and 6in in the back? also what parts should i use for this much of a drop and if possable could u tell me the total price id b doin the drop so labor is out of the picture the price anyway haha thanx n advance