My first full roll of PETG

Ok, I'm a little bit confused.  I purchased a filastruder a couple years ago (2.1d SN 3175) but just got around to putting it together recently and ran the first abs through it to clear it out.  My goal was to use it for creating PETG and bought some of the estar 6763 pellets from filastruder.com in anticipation.

Now after reading some of the posts here, am I reading right, that I can't extrude PETG pellets without modifying my unit?  People are talking about using custom nozzle sizes of 2.0, or 2.2mm in order to get 1.75mm filament?  I thought that's why I have a 1.75mm nozzle was to produce 1.75mm filament.  It seems like if it's shrinking that much maybe the temperature is too high and when it comes out, it's stretching due to it's own weight and being too molten.  Maybe better cooling as it exits the nozzle and a lower extrusion temperature?

Has anyone actually had success with PETG using a non customized filastruder?

Ok, so the real problem is that the motor is insufficient to properly extrude at what would probably be a better temperature?  So to compensate, we crank up the temperature to melt the PETG more than usual, which then causes extreme shrinking as it comes out of the nozzle due to the weight of the extrusion pulling on the overly molten plastic?  Not really that the filament is shrinking, but being stretched too much?

The reason I ask is because if you are using a 2.0 or 2.2mm nozzle to get 1.75mm filament, that's a huge amount of shrinking.  That's about a 12.5%+ reduction.

I guess that begs the followup question...  Do people see this kind of shrinkage when printing with PETG?  We're usually printing PETG at anywhere from 230-265C, so that would mean I would never get a true .4mm line from my .4mm nozzle, but rather .35mm or less. According to the MatterHackers website:

I'm not trying to be difficult, I just want to understand fully what the issues are so maybe I can find some possible solutions that don't require a lot of trial and error like drilling a new nozzle then hoping I can find a temperature that will give me 1.75mm filament.  Could finding a more powerful motor than the GF45 be an answer?  It seems we already might not be using the GF45 at it's full potential limiting it to 1.6A.  Maybe a stronger power supply so the GF45 can run with a little higher current?  Maybe better cooling as the PETG exits the nozzle?

I don't want Brucehvn thinking he can buy a more expensive machine and not have to deal with settings though.  Usually the more expensive the machine the MORE experimentation required to find all the proper settings - eg with an EX6 setup you'd have to adjust 4 temperature zones, a motor speed setting, a fan speed setting, a puller/traction speed setting, and nozzle size.

To try to extrude filament, involves settings, and the best you can do is take somebody else's settings and then adjust from there (like Murph's 205C with a 2mm nozzle, you start there, then adjust for things like ambient temperature, drop distance, etc. that are different from your setup and his).  The good thing is unless you are wildly off usually you can still use the filament produced until you dial everything in - just tell your slicer what diameter the filament actually is instead of 1.75mm.