The first thing you'll want to do is strip the important parts from the broken shell.

In Bearing Core's case this means the cap, shaft, bearing and tip. The process is simple, you simply pull the tip off as gently as you can. The shaft end keeping the tip in place is knurled, so under no circumstance should you twist this tip off, only pull.

When pulled off, you can pry out the Bearing that rests snugly at the bottom of the RC, and then pop the metal cap off from below by pushing up against it with a thin object.

This process is identical for Bearing Core 2. They share the same housing and components, the only difference being a slightly different tip design and material. 

In Grip Flat Core (Ultimate Version)'s case, the process is much trickier. The key component is simply the rubber tip, but it cannot be pried off so easily. The adhesive used to keep it in place is very potent.

One of the only realistic options is to simply destroy the plastic RC with your tool of choice. All the while making sure the rubber RC is not ruined or stretched in the process. 

After adequately pulling apart the plastic RC, make sure to pry the rubber tip off gently so that you are left with its natural shape, and no chunks are left behind in the old broken housing.

Note: There may be chemical options to loosen the adhesive on GFCUV, by prying open the cap and then dripping below into the shaft that holds the rubber tip. In my case, I simply destroyed the plastic component of the RC and diligently separated the rubber from it. For those of you with more brain power, there may be less brute options that have yet to be tried.

The hard part is now over, you have access to all the desired components and the new parts to house them in.

For both Bearing Core and Bearing Core 2, you put the metal cap into the top hole of the replacement housing, followed by the shaft, and then at the opposite end stick the bearing into its new hole and press the tip back into the knurled end of the shaft. 

Not a whole lot of force is needed, just good grip onto the tip.

For Grip Flat Core (Ultimate Version) as well as the original Grip Flat Core, simply put the plastic cap provided into the top hole, and apply your adhesive of choice onto the opposite end where the rubber belongs. You may want to consider applying it into the hole as well, not just the surface. Put the rubber tip in and wait the determined amount of time for the adhesive to bind the rubber to the new housing.

Note: It is also possible to use the original Grip Flat Core (Ultimate Version) cap in place of the reproduction one, but may require tapping it in for a tight and secure fit.

Probably the most common question regarding these new housing is whether they work the same and look the same.

In appearances, they all come in a stock white, and for clarity's sake the none of the new housing have been coloured to match the originals. In your personal collection, it should be fairly simply to paint these parts to match the original, intended colour.

As far as the measurements go, they're all equal to the original parts, but with the exception of a sturdier prong design than the originals. 

In terms of play, they act identical to the original RCs, so you can expect to bring back broken parts from the dead and have them play just like they did initially. 

In terms of weight, the new housing tends to be on the lighter end. Here are some examples:

Original Bearing Core weight: 4.07g

New Bearing Core Weight: 3.60g

Original Bearing Core 2 weight: 3.87g

New Bearing Core 2 weight: 3.60g

Original Grip Flat Core (Ultimate Version) weight: 1.54g

New Grip Flat Core (Ultimate Version) weight: 1.50g

While these weights are definitely different than the original, the deviation is not likely to have a meaningful impact on performance. You should expect identical performance out of them, not better or worse than how the parts were pre-breakage.