PP paddlewheel install tips?

I've got my boat almost ready for the water. All that's left is installed the paddlewheel for Perfect Pass. It seems very straightforward and simple, but I'm dreading this part. Just don't want to screw it up since I only get one shot. It's an '89 Saltare and I'm thinking to install on port side a bit to left of center right behind the last fin and kind of under the alternator. The hull is angled up but flat in this spot and I have about 10" between center of hull and where the stringer is. Want to be sure I get the measurement right since it doesn't look like I'll have any room to do a pilot hole from inside with the engine in place.

Anyone have tips on measuring, drilling the hole and installing the wheel?

go slow.
measure twice
drill a pilot hole first. make sure both sides look good.
drill from outside, in reverse until through gel coat.

If you measure right you can still do a small pilot hole from the outside it will be easier to fix than trying to cut the paddlewheel hole and having to fix that.

I tape up the area I was working on also.

Use a pair of magnets (one on the inside of the hull and one on the outside) to locate your pilot hole position. This takes all the guess work out. Check it numerous times for obstructions and for a flat surface (inside and out) larger than the diameter of the largest point of the paddlewheel. Make sure there is nothing in front of it that would obstruct or create turbulence over the water flow that goes to the paddlewheel. Tape area around outside magnet (where you are going to drill) with painters tape. As mentioned earlier, drill in reverse with a hole saw until you are through the gelcoat, then go to forward. Be sure your hole is big enough. If you are a bit small, it is a PITA to grind it out. Chamford the edges of the hole/gelcoat with a grinding attachment and dremel a bit to help avoid spider cracking (should not be a problem, but it's good insurance).

I'm not familiar with your hull. That is a direct drive, yes? Generally with a DD, I would locate it in the engine compartment, usually toward the front of the compartment.

Also, you may want to tape the inside area as well, or enlist some help to have someone press down on the inside around the pilot hole (taking care not to cut into the person). Recently, I witnessed the top layer of fiberglass pop up when a friend drilled a thru-hull for a ballast system on a MC. A little pressure from the inside would have avoided that problem.

Thanks for the tips guys. Got it done earlier today. I tried the magnets but even some rare earth wasn't strong enough... Hull was too thick. A good think I guess. I took some measurements and ended up 6" to port of the drain plug and 11" back. Used a abrasive hole saw as was recommended in another thread. It seems pretty good all installed. I used fast cure 5200 instead of regular 5200 as I'm planning on first splash this Saturday.

Odd... I have used both strong natural magnets and super magnets (each about the size of my thumbnail) and both worked on MasterCraft and Nautique hulls. I'm glad it worked out for you though.

Skip drilling the hole and eliminate the paddle wheel all together!!!

For $250 you can buy the GPS equivalent of the paddle wheel. Check it out on their website, nautic Laugic.

They are on ebay and you can use Pay Pal if you want. They are great to talk with on the phone and seem very helpful. I haven't ordered mine yet, but I will be soon.

GPS won't work for me since I ride on a tidal river. Current can be higher than 5 MPH at times (well, 4x a day). This is why I ordered the paddlewheel version. If I rode on a lake I probably would have got the GPS version for simplicity sake.