Just use the C64 tag around your text, like this:
[c64]**** COMMANDER X16 BASIC V2 ****[/c64]
shows up as
**** COMMANDER X16 BASIC V2 ****(If you're seeing this in Courier, it takes time for the style changes to propagate through the cache. Also, make sure you're using the Flat or Retro8Bit themes. The ProSilver theme does not have this customization.)
And if you really want to have fun, use the X16 tag. This gives you a blue background.
**** COMMANDER X16 BASIC V2 **** 512K HIGH RAM - ROM VERSION R41 38655 BASIC BYTES FREE
If you're curious, the new tags wrap text in the <pre> HTML tag and use the C64 Pro Mono font from Style. The font is used by license, which allows for embedding of the font in web sites. (yay!)
You can download the font from :
https://style64.org/release/c64-truetype-v1.2.1-style