How to change fuel pump

It was a complete unit and I been searching online the last few hrs and seen several times where the connector was mentioned as well. I know all he replaced was the fuel pump unit and nothing more so I will for sure mention this to him in the morning. And as for clearing the engine light, I asked two different certified mechanics if we should replace the O2 sensor that the code referred to and both of them said it wouldnt really cause any issues if it was left faulty and we could clear it using the code reader thing. And what is the freeze frame data? Ive never heard of that. And there has never been a problem with the blazer til the fuel pump went bad so that makes me think the issue now is somehow related. So thanks for the info and sorry I have more questions :)

Also.I wanted to ask what the chances are that the new fuel pump could be faulty? Ive heard the fuel pumps made, especially for the 2dr models as we have, arent considered all that great and getting a faulty one is actually quite common.

I am attempting to replace the in tank fuel pump on my 2001 Blazer. I have the tank ready to drop, but I can not remove the filler hose from the top of the tak. I have yanked, pulled and tried to pry it off, but no luck. Any ideas or tricks to get this thing off. Your help is greatly appreciated.

Thank you

Ok after talkin to him and us goin out and seeing what we could do. We know that there is no fuel pressure cause when he found the schrader valve there was no fuel that squirted out of it like it would if it had enuf pressure. We can hear the spider make somewhat of a clicking sound and I no that the fuel pump works so I assume that it is getting power. Besides a bad fuel pump what could cause the fuel system to lose fuel pressure?

There was a lil bit of gas that did come out but not what I no is required. So gas is present. So does that mean the fuel pump is working cause if it wasnt then shouldnt there be absolutely no fuel in the shrader valve at all? And the blazer fan fine with no problems for about 2.5-3 wks after the new fuel pump was installed so we know that it did work properly and the fuel system was functioning the way it should. Or am I just tryin to convince myself that its not the pump itself again cause it was such a hassle? :)