SNMP return value manipulation

Hello, I’m new to LibreNMS and I need a bit of help. I’m building support for a new wireless device. I made a new OS recognition and have some sensors working. I now ran into a small problem. The RX and TX frequencies I get via snmp from the device are not pure numbers, but are in the format "Tx=7777.750MHz ". I want to remove the Tx= and Mhz from the return values, but I can’t see a way I could do that in the ./LibreNMS/OS/ file. The WirelessSensor method does not seem to allow that and just wants to get the value itself based on the oid. What would be the best way to handle a situation like this? Any hints are appreciated.