ghettoWhere would I include the number that determines the size of the number in the name where delta_item_font goes?
I'm not sure I understand your question, are you asking how to make the font definition for delta_item_font_big bigger?
If so: the size of the font is determined by the "tall" value in clientscheme. So for gunblades m0rehud the default damage font is the same size for crits and for regular damage shots; they're both "M0refont23Outline". To make the crit font bigger simply put "M0refont24Outline" in "delta_item_font_big".
The reason the font called "M0refont24Outline" is bigger is because of the difference in "tall" values, hopefully this pic makes more sense than my shitty explanation.