Would have been easier to just buy a JWE ignition (old style 3-wire) instead - just plug and play.

If you insist on converting to the new style, you can send it in and we can update the hub for you.
This consists of two possiblities...

A) The old magnet can be drilled out and filled with aluminum putty and the two new magnets can be installed.
This only works if your case is drilled for the sensor mounting holes on top and bottom.
They you just buy the sensor and go.
Total cost: Sensor + 2 Magnets + Labor and shipping

B) This is what happens usually...
New Hub + Sensor + 2 Magnets + Labor and Shipping

The gain: You just added the ability to run NiCads and 2 Cell LiPo's with no regulator.
The New IIS ignitions also add a sleep mode where the ignition goes into standby and can be re-enabled by flipping the prop once.
It's a nice safety feature in case you forgot to turn off your ignition and some kid tries to flip the prop. By the time he gets to flip it on the inert first flip, an adult can get a hold of him to prevent a second flip when active. Should make the AMA feel all warm and fuzzy.

Kevin Schlosser
"PropellerHead"
Aircraft International