Cooling off the intercooler with water or a CO2 is going to do way more than wrapping your intake system or building shielding.
You all have to remember that we have to get the pressurized air from the turbo compressor as cold as possible. A 1* to 5* degree difference on the intake side will not make much difference since the turbo is compressing and heating the air up even hotter anyway.
Best way to do this? We need to decrease the temperature of the intercooler itself, or increase the heat transfer area, or both.
The intercooler is a heat exchanger and to get colder air out of the intercooler for our need for speed, we have to transfer more energy out.
If you increase the size of the intercooler to the right size (without adding lag or more pressure drop) we can transfer heat out of the pressurized air longer, resulting in lower temperature.
Or, we reduce the temperature of the intercooler core. We can spray it with water or colder air (or CO2) or it could do a lot better on a colder day with colder ambient air.
This is where water-air intercoolers work best, their downfall is more parts and more money to install/implement them.
The larger the temperature difference between the core and the charge air the more heat will be transferred from the charge air.
No amount of shielding or gold tape is going to do what direct contact with cold water or another fluid will do to the intercooler core.
Water sprayers will help some, but they are obviously not ideal. With a FMIC, you take the core farther away from an ambient heat source (the engine) and you increase cooling area (larger core).
If I were you all, I wouldn't go wasting money with a bunch of tape and metal panels that will probably add no temperature benefit to the system at all.
Ice or spray the stock IC, or get a properly designed FMIC or water/air IC. I'd like to build a water/air IC one day, it would be different