The first thing you need to do is remove the old wheels and wheel assemblies. For Maisto this means the wheels, assemblies, and springs from front and back.
REAR WHEELS: The rear wheels are simple for any car. Drill a hole just large enough for the axle at an appropriate height through the chassis, insert the axle and twist the wheels on. I find it helpful to put springs between the wheels and the chassis to keep the wheels from drifting left and right.
FRONT WHEELS 1: Repeat the above process for the front wheels.
FRONT WHEELS 2: By exchanging the interface between rims and assembly from the Maisto wheels you can simply attach the Dub wheels onto the original assemblies.
The black part is cut from a Maisto wheel, the chrome part of a DC wheel.
This sounds ideal but you'll need to cut apart the original rims as well as part of the new rims and then do some gluing. This may not work for all projects but produces a fairly good fit and lets you retain the suspension abilities.
FRONT WHEELS 3: This is more complicated still but produces good results. As of right now I'm the only person I know to have tried this. Get some flat space on your chassis. You may need to cut off some pillars or extra plastic to do this. Once you have, drill a small pilot hole and screw in an eyebolt (see pic). The eyebolt is threaded and thus can steer. Make sure to choose an eyebolt that isn't over-sized or too small, it has to fit the wheel.
Next you'll need a screw, a washer and probably a spring for each wheel. The screw will go into the wheels to prevent it from rolling right out from under you car. The washer (or hex nut) serves the function of stabilizing the wheel and preventing severe camber from appearing. The spring, if needed, keeps the wheels from sliding into the chassis.
You may need to double up on washers or springs to achieve the desired effect, this process is gonna be based on the car and the wheels. It may take some time to adjust all the parts correctly but this flexibility allows for some nice customization of your diecasts stance.