bounding box

I have to make these fonts for my boss who thinks because I do graphics I can do fonts.
She wants these fonts to be upper and lower case true type, I have already made the glyphs. They don’t want them kerned thay want the space created by adding white space to each side of the gyph.
they want at 100 Milimeters to have a 3 milimeter on each side of uppercase letterA and 9 milimeter on each side of uppercase letter C and 11 milimeters on the left of uppercase B and 6 milimeters to its right, ect. As I look at other fonts I get so confused on where to set my settings ( Asent, decent X and cap height and so on) and what size my em square should be? All help would be appriciated and this master of mine has threatened to fire me.
I have never worked with fonts until the last couple weeks

Hank

One approach is to find a font from a reputable source to use as a template and then replace its glyphs with yours.

You might not have to redesign simple things like brackets, accents etc. Choose a font that already has all the mappings you need (Macintosh, Microsoft, Unicode etc).
I would add guidelines to correspond to the fonts x-height, highest ascender and lowest descender to help you position (and maybe stretech or shrink) your own glyphs.
You must look into Namings to find and change any reference to the former owner of the font.

Mike