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Think it may have only been a dying battery! Good noises with a fresh battery so I'm going to play with it a bit more and hopefully everything is good now 

I hate to keep reviving this thread...this pedal has been a real paint to debug.  Now I feel like I'm really close but I'm having another strange problem.

When I test the board, it works fine until I turn the mix up and the feedback up and then comes this ridiculous screeching/squealing that does not go away.  Even when I turn the feedback down it is still there.  Oddly enough, the volume of the screech seems to be controlled by the mix knob.

Here's a video...

Ok I changed r3 to no avail.  The volume is really low and I have to crank my amp.  The signal isn't good and my amp settings don't sound correct.  If I really hammer on the strings I get more volume.  I figured that would point to one of the transistors or the opamp.  The transistors all still look like they're getting good voltage.  But my tl072 looks a little different.  I'm getting:

1 4.03
2 3.67
3 3.96
4 0
5 3.93
6 3.95
7 3.95
8 7.82

Is pin 2 too low? Also, the voltage on this new battery has dropped fairly considerably since I started testing as you can probably see from pin 8. Any ideas?

By the way...Huge thanks to you for your help, Rob! 

Alright, I've got some real weirdness going on here, but I think I've made progress.  Like I said before, there was continuity between the output pad and the 9v (new battery, output pad @ 9v). The output capacitor seemed to be doing its job when I had previously taken it out and measured it while it drained with a multimeter. 

Here's the weird part...There was no continuity between the output and the pads to either side of it. I cut the trace between the output pad and c3, so the output pad should have been completely isolated on the board, but it was still getting 9v!! Wtf? There is a 9v trace that runs by that pad, maybe the trace is touching the pad on the pcb?? I have trouble believing that there could actually be something wrong with the pcb, though. Anyway, I ran my output wire from the leg of c3.  Now the signal is there and the pedal is behaving as it should, BUT it is too quiet. 

I did use 470k for r3 which is supposed to reduce the dry volume, so I think I will change that, but it still seems like it is much too quiet considering I have my amp cranked up pretty high.

Measurement is in volts. I just measured my 9v battery and it is really low (~5.1), so the output pad is receiving the full voltage of the battery. All the wires coming off the board are all f*cked up from messing around with it so much out of its enclosure.  I think I'm going to build a testing rig and pull these wires out of the board. 

C3 is suspect, for sure, but what I don't understand is why I have a ton of dead pads and radio reception all over the right side of the board if its just a bad output cap. 

This pedal is driving me crazy!! 

Voltage at ouput is 5.13.  The two transistors are both BC550's.  The regulator is L78L05. There is no continuity between my output and ground.  I posted a picture earlier in this thread of the pads on the pcb where I get a signal with and audio probe and where there is nothing/radio...that might be helpful (??). 

Thanks for helping!

Well...Still no joy.  I replaced both of the 2399s and get the same problem. I will take a look again at my transistors.  I don't remember if i mentioned it somewhere earlier in this thread, but removing the sockets and soldering the transistors direct to the board was one of the first fixes I tried because they didn't feel secure in the sockets.

Took out the 2399s and I'm still getting signal at c3 and very very low signal at output.  When the ICs are out, though, the quality of the sound is different.  I don't hear the echo--just clean signal.  I don't have anything to swap in for them.

I just got a new soldering station that I'm really pleased with, so I was super confident with my connections. Lol...that's the way it goes, I guess.

It wouldn't have anything to do with leaving out r30, would it? That's what was recommended in the build guide. Maybe need to jumper or something to connect that ground pad? Idk.

Thanks, I've checked those pads for bridges and reflowed with no luck.  I don't have a replacement for c3 laying around, but I will replace it as a last resort...I'd just have to make a trip up to the electronics store tomorrow probably.  Any ideas that would explain all the dead pads and radio interference on the right side of the board?

Ok, here is the result of some audio probing.  Blue dots are a good signal.  Pink R's are radio reception. No dot means nothing is coming through there.  And I have already mentioned the very weak signal after C3. 

Resistor band values are all correct.  IC socket pins all appear to be coming through the board and soldered in place.  Should I try taking them out and soldering the ICs directly to the board?  But would the voltages show up apparently correct if there were a problem with the socket? 

I'm going to do some extensive and methodological probing and voltage testing and I will post my results.   

yeah, all 3 are socketed. voltages are in an earlier post.

Thanks for the help so far, guys.  The output jack is not grounding out.  The signal at the output is very very faint, nothing at ground.  Also, it seems that at C3 where I am getting the signal it is only the echo, not the picked note.  When I probe the transistor leg closest to the ICs I am getting radio reception through the amp.  That happens for both transistors.  Same symptoms outside the enclosure. 

I will go through and recheck my resistor band values.  That takes me awhile... Any other ideas?