Larry-------How are you laying out the seat? I made a pattern in the shape of the seat with all the hole locations------spindles, posts, legs, etc. and drilled small holes at each location. I lay the pattern on the seat blank and use an awl to push through the holes in the pattern to transfer locations to the seat blank. It also includes sight lines to aid in aligning the holes. With the legs I use the sight lines along with a T bevel set to the appropriate angle to get the rake and splay of the legs.
If you are using a "plan" from a book or magazine you may not have all the information you need. I have experienced mistakes in book and magazine plans---errors do occur in the process of writting books and articles----and not always caught before going to the press.
If this does not answer the question just give me a shout and I will try again. I do not have all the answers but can tell you what works for me.
BTW--------It looks like you are doing a great job on the chair. The more you do the clearer things will be for you. Practice makes perfect---I still have a lot of practicing to do.
Jerry
