There was additional information on this page, basically a mirror of a page describing a tv to game tube swap on Coinop. I was asked by one Kurt Koller to just link to their page instead of replicating it here. Since the info was duplicated here only to help other interested  parties and archive it,  it has been removed. BTW, though I was told the info will always be available, I'd like to point out there were 2  site links on this page to additonal tube swap info now dead , the info lost. (those links removed as well)
I beleive there may be 2 new links available, check the above site.

If time permits I will document my own tube swap here.

Additional Information (

Be advised not all monitors are created equal. Meaning that swapping a CRT from a TV set to a monitor may not work out well in all cases. The big problem that will be encountered will be getting the dynamic convergence correct (non center area of screen) and the geometry.
This is because of differences in the Yoke/tube combination. Some of these problems can be corrected by adjustments on the chassis but not all game monitor chassis's are equipped with a full range of controls. Some have 3 position wires for example instead of a control. Some monitors have a very limited range of adjustment while others are very generous in what can be corrected. The alignment of the yoke will be critical in determining what your finished picture will look like. Besides the up and down tilt of the yoke, a certain amount of diagonal force to "warp" the yoke a bit, may be needed to correct errors in dynamic convergence. What does this mean. Simply, if the dynamic convergence is off, lines,characters and graphics will exhibit a color "ghosting" on the edge reflecting the error. How bad it is will be determined by how big the error is and what color is in error with relation to the graphics/text being displayed. For example if the game you are displaying shows a RED border line drawn around the screen and the error is in the red it would not be noticed. But if the border was white then you would see a red ghosting on the edge. The same thing would happen for white text, it would look like it has a red shadow.