Sticking gas pedal, It's like driving with cruise control Options

[EJP914]

Have 1.8 with sgl carb. Backing off the gas, the pedal will not completely release. There is about a 1/2" of travel before it completely comes to rest and the engine returns to idle speed. I have to pull it back with my foot to get it all the way back.
I have replaced the accel pedal (old one all rusty inside) and put in a new accel cable thinking the old one is was all gunked up. Neither of these helped. The accelerator action is just not very smooth and the gas pedal still hangs up.
What else can I check?
I have sprayed the accel pedal bushings with PBBlaster thinking that may loosen things up, but no luck.
If I replace these 2 bushings, can it be done with the pedal cluster in the car?
It doesnt look too bad looking at the Haynes manual. Take out the cotter pin on the end and the pedal pivot should come right out? And then take out the 2 bushings?
This is very frustrating and I am losing good driving days. Your help is very much appreciated.
Ed

[EJP914]

Thanks for all the suggestions. The cable slid in thru the tube without any problem and the pan looks good - not caved in or cracked undercoating so I don't think it was ever lifted in the middle.
I looked down the tunnel with a mirror and the cables are not caught on each other. The accel cable is parralel to the clutch cable below.
I have lubed all ball/socket connections.
I see how the accel cable could get caught on the clutch cable clevis but my accel cable is stretched taught so it doesnt hang down at all.
Any other suggestions besides replace the plastic bushings? I thought a lighter throttle return spring might make a diff too?