How long does it realistically take to study for the ASVAB?

I've got exactly eight weeks before my scheduled test date and I'm starting basically from zero — I've been out of school for three years and the math and science sections feel rusty. Is eight weeks enough to go from a 40-something to a 70+ AFQT?

I've mapped out a rough plan: two hours a day, covering one subtest focus area per week. Week one is arithmetic reasoning (I found the ASVAB Arithmetic Reasoning Test 2 here is a good benchmark), then math knowledge, word knowledge, paragraph comprehension, and then full practice tests the last two weeks.

According to most asvab study guide resources I've read, a 30-point AFQT gain in eight weeks is ambitious but doable if you're consistent. The key seems to be identifying weak areas early and hammering those specifically rather than reviewing things you already know. Anyone improved by 25-30 points in a similar timeframe?