May I recommend that you don't do the repair this way---if the boot is torn (and there are two per axle, so with the axle out you have to replace both of them), then there already might have been damage to the CV joint itself. Also, the labor to replace the two boots is 1.9 hours + the cost of the two boots which is $85.
For probably LESS or the same money, you can install a "half shaft kit" which is the complete axle with rebuilt CV joint + the boots. So it's a complete axle with all parts, just ready to bolt in for the same labor (or even less labor) than replacing the boots.
you can price out the half shaft kits at ROCK AUTO...click on Nissan, then Altima, then 1999, then "drivetrain" then "half shaft kit".