when i changed the oil in my outdrive I had to take the 4 locknuts off that hold on the plate for my hydraulic steering to be able to access the top plug. after i filled it with oil and put everything back together i have a slow leak from one of the lower studs. is there an O ring or something that maybe leaking? what do I need to do to remove the drive to fix this?

If your loking at the drive from the rear is it leaking from the lower right side stud. If so I suspect it will stop on its own. When you had the stud nuts loose the resevoir fill connection probably leaked some gear lube that was caught in the stud passages. A little gear lube goes a long way. Torque all mounting nuts to 55 ftlbs, then remove one at a time, spray the stud and passage with brakleen to flush out residual gear lube, re-install and torque each nut, then check it the next day.