Also trying to get the Chris Cuff AM stereo transmitter to 50 ohms

I am also trying to get the transmitter to drive a 50 ohm load but not for an amplifier but rather a custom built antenna that follows the part 15 standard. At the moment I have a series L/C circuit connected to the output which is slug tuned and it seems to be working ok but I figured I would ask about this. Currently it is hooked up to an MFJ antenna tuner to do forward and reflected power measurements but shows neither (likely not sensitive enough) that is unless I adjust the transmitter and antenna loading capacitors then it will show weird levels of forward and reflected power. Any ideas on how it can be made to drive a 50 ohm load?