I have a FT1000MP I have been running on 160 m. driving a leenyar for the past 10 years. On AM it used a dinky little Murata ceramic filter in the 455 kc IF stage to limit AM bandwidth on tx and rx so it would transmit space shuttle audio rolling off at 3 kc. I yanked that sucker out and put in a wire. That gave me an AM exciter that could be run like a broadcash rig (i.e. no audio filtering in the rig at RF) with any audio roll off imposed where it ought to be at the processing gear. On AM rx it meant the plastic radio was barn door wide but I didn't care because I used my separate receivers anyway. Maybe this is an option for this FT3000 box? My experience with my 1000MP if it is anything to go by, is that running a plastic radio on AM pretty much sucks compared to a regular plate modulated rig. It's a lot easier to mess around with the audio in a Ranger for example. you can get it out of its cabinet and bolt it to a wood plank and then arrange out board parts like decent mod. transformer and driver transformer and have a 40 watt rig if that's the power level you want but build up the modulator, maybe even use a small reactor. The plastic radio here has an RF carrier that is constantly drifting up and down. I'm told it is a design flaw. The rig was clearly intended for slopbucket.