Body Fat Prop Bet - Need Advice

[widemanb]

My wife, a few friends of ours, and myself are about to embark on a 2 month prop bet, but I am in need of some sort of "equivalent" across the diverse group. Here's some details:

1. Some want to lose, in fact, everyone but two of us want to "lose". Myself, being 175 lbs and 11% body fat is more interested in gaining actually. Lean mass, not any additional fat.

2. We have a few guys and a few girls. The body fat scale is obviously much higher naturally for girls. This causes problems because we just can't say, "everyone has to lose 5%" because for me that would mean getting down to 6% which is totally outrageous compared to one person in our group who is a girl with over 35% body fat.

3. I thought about doing "you have to lose 10% of your body fat" but even this poses problems. someone with 35% has to lose 3.5% which is simple in 2 months time. However, 2 girls are around 23% body fat. losing that extra 2.3% is actually quite difficult.

4. I want to gain. I want to put on lean mass, somewhere in the range of 10-15 pounds eventually from my 175 current weight. I can't say "Ok you guys lose 10% and I have to gain 10% lean mass" because that means I would have to gain like 15 lbs of fat free mass in 2 months, obviously nearly impossible.

Without exact stats from each participant does anyone know an equal scale we can use? Ideally we want the "difficulty" of each person's goal to be the same. Also, how can i participate since I want to gain lean mass, not lose body fat?

Any advice on how we can structure this bet is appreciated.

Thanks.