So as mentioned in an earlier post *here* and *here* what I suspected was true, I am able to get to 432 MHz with just a few addition components. A Mini Circuits MK-3 Frequency Doubler, and a ZX05-1L-S 2-500MHz Mixer.
As shown in the photo above the Frequency Doubler goes at the CLK0 port of the Si5351a Etherkit Breakout Board. I set that for a CONSTANT 150 MHz out carrier behaving as an "LO". Out of the Doubler it comes at 300 MHz and that runs into the LO port of the Mixer.
I then set the beacon code in the Arduino Uno to generate KEYED 132.312.5 MHz on CLK2 port and that runs to the IF port of the Mixer. The sum of the two = 432.312+ MHz output. That runs in the photo to a 100 MHz High Pass filter and into a ZHL-1A-S 1.5Watt amp. That then just runs to a dummy load that's sitting on top of a HackRF One with a wire plugged into it's antenna port a draped over the dummy load just so I can verify the output is where I think it should be.
Here's a video of it operating: