The very simple method for posting chords, or other "aligned" type, is simply to lay it out in a monospaced font like Courier in your word processor, and the use the "preformat" tags when you "paste and post it."

If you tack a "<pre>" tag on at the beginning, and close with a "</pre>" tag at the end of the stuff that's aligned, the stuff in between the tags will keep all the spaces and line breaks just like you typed them, so you don't have to code a lot of non-breaking spaces in code, and it will be displayed on screen in a monospaced font.

If the alignment is off after you copy and paste, just select the section and change it back to whatever monospaced font you like, and the alignment should be as originally laid out.

  C              G      F       C
  Sweet fa's the eve on Craigie burn and
  Am       Em        G   G7
  Blythe a wakes the mor-row

There's no way you can use "fillers" in any proportional font and be assured readers will see what you intend, since they get to pick their own display font and different proportional fonts have "different differences" in the character widths.

John