Yeah, I took covert measurements of her pants, waist, hips and length, women's size-wise as well as in inches. Its a bit ambitious, I give it a 50-50 chance of success. Anyway, we call each other fat-ass all the time, so no worries.
Thanks for the recco, myhondas. And the advice, MickeyX.
If all else fails, maybe I'll just get her a sampler pack of degreasers and chrome polish. You know, something girly.