Poor throttle response after replacing return lines

[Theaxehand]

Got the selector valve all squared away and still the same issue.

I can blow through the return line to tank but there is resistance, should the line in the tank be blowing bubbles in the fuel?

Any chance I could have a clogged filter screen on my pick up tube and I’m simply not getting enough fuel at the IP?

 

[Selahdoor]

Yes.

Also possible the vent line for the tank is clogged up.

 

[Theaxehand]

I think my next move is to drop the tank and replace pickup and lines.

Should the tank end of the return line be submerged in fuel?

 

[IDIBRONCO]

Should the tank end of the return line be submerged in fuel?

Yes but it doesn't go as close to the bottom of the tank as the pick up does. In this picture, this is the sender from the factory rear tank in my Blue Truck. I've pulled the shower head off in this picture, but the return is the one with the orange thing at the end of it.

 

[Theaxehand]

PROBLEM SOLVED:

After running through the fuel lines and selector valve, I still had the same issue. Popped the top off the IP and had a stuck metering valve. I gave it a good soak overnight and worked it free this morning. Hit the key and she fired right up and problem gone! I had previously done the ATF overnight soak with no results, I didn’t open the IP that time because it was only a month old.
Thanks for all the advice and info, I really appreciate it!