Latex formatting paper size and eqn, figure, and table numbering in book

I am working on a "book" written in Latex that I need formatting assistance with. This is a 50 year old text that I am converting to Latex so I am trying to keep as much of the original style as possible. I am working on a Mac with the Latexian editor. There are two areas I need help with. 1. Setting the paper size and margins for US Trade 6" x 9" paper. I plan on using one of the online publishers such as Lulu or Amazon. Right now I am using the "geometry" package but it is not looking correct. 2. I am using the "book" document class and have 7 chapters with approximately 45 pages total. If possible I would like to continue using this class as the page layout etc. works well. a. I need to have the chapters as Capital roman numerals. I am using the command "\def\thechapter {\Roman{chapter}}". This is working. b. The numbers for the figures, equations and tables I need to run sequentially from the beginning to the end of the book. For example there are 61 equations that need to be numbered 1 to 61. With the book class the numbers for the equations, tables, and figures are restarting for each chapter and being preceded by the chapter number. For example, I.1, I.2, I.3, III.1 and III.2. The numbers also need to show up correctly when I reference them. ## Deliverables I am adding an example of the equation numbering.