Have Boat Questions? Ask a Boat Repair Expert.
As for the owners manual you can get it downloaded from here:
As for the holding tank, I suggest you get one from a nearby marine store as to get the origional one will be very difficult due to the age of the boat.
As for the painting, ideally he will start by sanding down the original paint and see if the scratches go and if no he would need to repaint it. Normally a good sprayer would know what needs to be done with the first inspection, but scratches normally go with sanding.
If you require further assistance feel free to contact me.
Unfortunately i do not know the exact dimensions of the tank but normally what you need to do is to get the approx volume of the area and fit a tank there. If you need the exact dimensions of the tank then please advise and i will opt out maybe someone else can help you.