If I buy the MegaSquirt PNP kit do I need to do ANY of this re-wiring/soldering for a 90-93 1.6 without a/c and p/s? It is also plug n play in terms of the wiring harnesses so a swap back to stock is doable, right? Thank you.

the only thing extra you'd need to do is wire in an intake air temp sensor if you plan on removing the AFM. Hence, PnP

That's correct-- if you're leaving the AFM in place it's fully plug-n-play, all you do is run a hose for the map sensor. You can check out the install section of the manual at www.megasquirtpnp.com

If you delete the AFM, there's two wires that plug into the AFM for your new IAT sensor since you deleted the stock one with the AFM.

Thanks for the quick response.

I really would like to build a DIY turbo setup but I'm a bit short on know-how so things like "PNP" are of great value to me.