Do you perhaps have a type bar that has a slug loose on it, and you want to remove it to clean it before you re-solder?  Or do you mean to remove the type face "style", meaning an en masse change of all the type bars?  If you stay within the type size, all you'll need to change are the type bars, but if you, say, for instance, want to change an elite type machine to a pica type one, you've got your work cut out.  I changed a 1958 Underwood SX-150 "Golden Touch" from an elite to a pica, and not only did I have to change the type bars, I also had to change the entire margin mechanism, tabulator mechanism, escapement mechanism, backspace mechanism, and all the scales.  When it came out, it type fine, but it did't feel like the same typewriter somehow.  I eventually sold it.

It wouldn't be an Imperial if it wasn't modular.  Too bad the quick-swap basket wasn't a feature carried over to its later portables. The standards on the other hand...

Here you go!