Spektrum compatible vs PPM encoder channel assignment

The latest challenge setting up my Pixhawk 2.4.8 Christmas present on the bench is inconsistent channel assignments between my Orange R820X V2 receiver and the PPM encoder I received with the kit. The encoder documentation specifies that the channel assigned to the PPM output for throttle is obligatory on Ch. 3. The throttle output from the receiver is on Ch. 1 and can’t be reassigned on my Spektrum DX9 transmitter. The output connector on my encoder is an itty bitty 10 pin connector.
I can’t swap wires at the encoder without tedious cutting and soldering tiny wires, and I can’t swap channels on the transmitter or receiver.
I could attach a photo for clarification if somebody can educate me on how to do it on this forum.
Thanks for any help

Connect receiver ch1 output to PPM encoder ch3 input, possibly transforming or making the appropiate wire (2.54 to 1.25?). However, universally throttle is already on ch3.