I know I ask this alot but , how about some pictures?
I used to do nothing but boats, Real big boats using gallons of wax @ a time.
Here is the procedure ,tried & true.
As far as the bottom anything ,unless specially designed to withstand being in the water ,most waxes will dissipate in a few hours & you will have worked your arse off for NADA .
Step #1:
If the boat is a yellowish shade 9 out of 10 times "ON / OFF" by Mary Kate will take any rust & yellow stains off.
Extremely toxic it must be squirted on in a uniform way I use a small squirt cone that comes with the Quart bottle.
Then can be moved around with a soft long handled brush DO NOT LET DRY . Best done in the early morning before its too hot & applied onto the glass when it is dry to maximize its cleaning effect. Do small areas @ a time until you are comfortable with it.
Wear GOOD rubber gloves & maybe a paint respirator,WASH off yourself immediately {trust me you'll know if you get a drop on you}
Step #1.1:
Compounding .
{When I 1st started detailing we did this by hand try that on a 70' sport fisherman!}
Yes me tough like BULL! {back then} LOL!
WHITE compound! its tough to find it in quantity but it has the best grit for the job, if not then start with a mild compound , If needed move up to the heavy machine compound . Make sure the Orange color is not sucked up into the pours of the fiberglass & leave you with a bunch of Orange stains.
Step 1.2:
Wet Sanding.
If all that has not brought up the desired color,depth & shine with a good cleaner wax then Wet Sanding is in order.
Its a lot of work I have only had to do a whole boat once & I worked my Arse off & did not charge enuf , but I digress.
Step #2
Then a good Old School Cleaner Wax .
Wax On ...Wax Off .
Cleaner wax is a must on Fiberglass the stuff I use literally get into the fiberglass dissolves the small particles of dirt & when it flashes brings the dirt to the top of the wax to be removed in the flake.
Step #2.2:
Sometimes in a rare occasion 2 people are needed to remove the wax while wet working small areas, {can be done with 1 person but a a double boat load of work your arms will fall off}
Step #3:
Re Wax with a hard Old School Wax.
Like I said this is a Old School method that works each & every time.
The problem with the Old School Cleaner Wax is its soft & does not last long.
I found that if I used a really hard wax right over what I just did my wax job would last 6 to 10 times longer with the cleaner wax only lasting 1 month in the rainy seasons.
Step #4 :
Maintenance Washing with car wash & nothing else will help keep the job lasting longer.
NOTE;
This is the method & products I use till this day .
Now, I know there are a lot of new school products that have made detailing so much easier & I have not tried any new "experiments" with the new product on boats , they could be compatible & maybe not. sometimes trial & error is a great learning tool.
If you have any Questions about what I wrote feel free to ask me.
What exactly is Collinite ? is it a permanent sealer?
SR66:bigups
Just adding some finishing touches that I think will help the boat look better, longer. I wish the previous owners hadn;t beached the white hull on (apparently) concrete boat docks. 
