Fueling & Injection - how to check for a bad tank of gas?

Hey guys,
So my dad has a '94 trans am that he hasn't started in almost 3 years now.. It's got a full tank. I tried getting a small hose down the filler neck but gave up after 30 minutes of trying.
I've read that using under a 3/16" hose, you can eventually get it in and siphon some gas out. Are they any easier ways?

Can I just disconnect the fuel line at the input to the filter, turn the car on for a few seconds, and just let all the fuel dump out? Could a bad tank of gas cause damage to the fuel pump?

Just trying to figure out the best way to get some gas out to tell if it's really bad.
Chances are that it's bad at this point, but is it ill advised to try to start the car? could a bad tank screw up the injectors and/or pump?

thanks
Jim

i suggest you drop the tank and clean it

there is a female electrical connector by the ecu that when powered primes the fuel pump, if you remove the fuel filter and power that plug you should be able to drain most of the tank

then drop and clean the tank as mentioned above