Andy - be careful when choosing the quick connectors. If Tohatsu are anything like Mariner there seems to be several types of quick in-line connector that on the face of it look the same, but I have found that some have a long locating prong and some short, and even when you think you've got the right one, some make a better seal than others. If you intend to leave the fittings on the tank alone and simply slide on the tubing, it's advisable to secure it in place with a jubilee clip (stops it leaking too). make sure you get stainless steel and the best type have rolled up edges so that they don't cut into the tubing. If you haven't fitted the tank yet it may be preferable to have someone fit a dedicated male fuel fitting on to which a female quick release can be pushed. That way you can use the standard fuel tubes that come with a priming bulb included (and it means you can carry a spare that you can fit in seconds in an emergency. You might also want to route your fuel hose through a water filter.
Could the other connector (the larger one) be for filling the tank via a pipe?
65 litres eh? You can get a long way on that with the Tohatsu 4 str