|From Stanley's 1898 Catalog|
There is not all that much information available on how to use the Stanley 55 Plane. Here is the short list of sources that have been useful for me:
The Complete Woodworker, Bernard E. Jones. Chapter 18 contains more than 20 pages of information on the use of the "55".
Planecraft, Hand Planing By Modern Methods, C. W. Hampton & E. Clifford. Chapter 14 has 20 pages on the Stanley 45 plane.
The Stanley #55, Understanding an ingenious workhorse, Gregory Schipa in Fine Woodworking #38, pp. 89 February 1, 1983
Mechanical Marvels or Steampunk Sporks? Roy Underhill. Popular Woodworking, December 2013.
The Woodwright's Shop with Roy Underhill aired an entire episode on combination planes on 9/7/2013. This episode is available online through PBS.
The Superior Works, Patrick's Blood and Gore, has all the information about the parts you need. Be forewarned - Patrick is not a fan of this plane.
A reprint of the Stanley 55 manual is available here:
If frustration sets in with the Stanley 55, I then recommend:
The Complete Book of Anchoring and Mooring, Earl R. Hinz, or
The Art of the Paperweight, Lawrence H. Selman