Re: removal of lower unit
Pulled my lower 6 times last week (don't ask)
Pull the starter off(DISCONNECT BATTERY FIRST) and you will need a 1/4" ratchet and a long extension with a swivel, memory serves the bolt is an 11mm, as stated it is directly under the front of the motor,standing behind the motor it will be on the left side, once you pull the starter you will be able to see it.
you want to pull the bolt facing you, not the one facing the front of the boat and as stated put a bolt back in the lower to keep it from dropping.
I found a trick to reinstall the shift bolt, make sure the lower is in gear before you try to put it back up(pull the shift rod up)so you can align the drive shaft splines by turning the prop, pay special attention to the water pick up tube, i put some grease on mine to help it slide on, if you don't get that lined up you'll just be pulling it apart again, once you get it together to line up the shift rod and the hole there is a small break between the lower and mid on the front of the lower where you can get a pair of needle nose vise grips on the shift rod to raise/lower/turn it to help line the hole up.
it helps to have someone on the throttle to line it up.
Also put a little heavy oil or grease on the new impeller just in case you missed the pick up tube, this will keep you from smoking the new pump.
The shift rod is by far the worst part of this job, the needle nose trick really helps with this.
if you have any problem post again, the only dumb question is the one you don't ask.