O.K., first of all I would like to ask a favor, finish filling out your user profile, your location, if for some reason you don't want to tell us your location, give us an idea, of the region, I'm assuming you're in the US. Also put your watercraft(s) in your profile.
The first thing you need to do is download a service manual for your boat. You can get one from this site if you join as a premium member or you can just google for one and download it elsewhere. To join as a premium go to the main page, click on premium member resources, and just follow the prompts.
The following is based on the fact that the boat was running and properly winterized when it was put in storage.
If your boat still has grey tempo fuel lines they must be replaced with black automotive fuel hose your boat will use a mix of 1/4" and 5/16" hose, clean the fuel filters, especially the ones in the carbs., clean or replace the fuel selector valve.
Dump the fuel in the fuel tank, even is stabil has been used after 4 years it's bad. Fill the gas tank with 5 gals. or so of fresh premium gasoline.
The oil in the injector tank should be O.K., be sure it's the correct oil, use API-TC rated full synthetic. The injector oil system will probably need to be serviced but lets see if we can get the engines started and what kind shape the motors are in.
Install a couple of fresh batteries and see if she will start. If she starts don't run the engines for more that 30 seconds. If you're lucky and get this far post your results.
Lou