... I could use the BCD to compensate for the weight, but thought that was not a good practice to follow.
At 6' your lungs should be big enough to compensate for those few pounds, but why? It may be just me, but I find it much more relaxing to be a couple of pounds overweight and not have to exhale all the way while finning upside-down at the safety stop. (I've actually done that so I know I can.)
As others suggested, get a soft plate to shed a couple of pounds, though I suspect your "calculated" numbers are a bit off and you'll be fine with what you got. (I'm 6'1" and used to weight 185 lbs and your AL80 numbers sound about right and I'd guess you won't be 8 lbs overweight with a steel 100.)