I'll add in what I had to do to get my 4G61T setup to pass emissions back a couple of years ago - change my catalytic converter. A 4G61T does not share the same timing maps per se, but it shares the same architecture, had many 1G exhaust parts installed at the time, and will be running at the low part of the timing maps and out of boost just like a 2.0L would
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I converted the whole car back to stock parts from mostly 1G components (14b with ported 02 housing stayed) and fuel control, and even had redone the HG and cleaned up the head completely, so as to know what I was starting with. Compression was good enough to not worry about, but the smell out the tailpipe had me worried all the same. EGR was hooked up and was confirmed working as it should. Only problem I thought the motor had was low vacuum, it sat around <15 in/Hg at warm idle.

My test thread at 4g61t.org complete with readings, 4G63T setups should be similar in full stock form: http://forum.4g61t.org/viewtopic.php?t=17247

So with stock ECU, MAF, CAMs, but an aftermarket 2.5" catalytic installed by the PO, I still failed miserably. Fuel which was ~1 year old 94 Sunoco octane, and the next test showed that new fuel did nothing to change things either. So, I began to contemplate what would bring down all 3 tested emissions but only after reading through the 90 DSM Tech Manual did I find, that the DSM catalytics are designed to reduce all 3 emissions, in combination with EGR working properly too. So the hunt was on for a 3 WAY CATALYTIC CONVERTER with or without the pipe off the side that remains plugged to this day (it only gets utilised on air pump equipped vehicles anyways).

$79 plus taxes later, I had a Flowmaster 2.5" high flow aftermarket catalytic (universal) ready to install. Ran another E-test with my cat welded at the front (so as to not turn it into an afterburner undervacuum circumstances), clamped at the back, and a weld where my muffler inlet was letting go from age, the car passed with flying colors!

Morale of the story, install the EGR and catalytic you removed, and or play with your timing and fuel, but be aware that a low function catalytic will not let you pass no matter how hot it is, nor what you do with the fuel system. You will take your spark, timing, and fuel systems out the proper range of control (misfires, etc) because you can't make up for a the work a properly functioning catalytic will do at reducing/converting your carbon dioxide, NOx, and Hydro Carbons.

P.S. I spent $750 dollars CDN, to do this the legal way and to know for myself what it takes to get a DSM style motor combo to pass E-test properly. I have a baby boy that will inevitably sit in the back of my car, and I would be doing him and the world an injustice by filling him full of exhaust fumes. Since I performed this experiment, I have become an E-tester on top of my other duties as a technician, at the same dealership at which my car passed. The world works in strange ways, but this doesn't have to apply to you!