Flexible RV mounting options for 40G/20G

Hi all. I’m new to the forum after a long and difficult time trying to decide between router manufacturers. ( the router model still remains outstanding but that’s a slightly easier battle!)
I think I’ve settled on one 40G for cellular and one 20G antenna for Wi-Fi as WAN only. (I want to maximise WiFi capability as as this will be my primary mode of connection).
Assuming that a maritime antenna will work equally as well mounted on an overlander, what mounting solutions would allow for a fold-down? I would nt want it much higher than the poptop for containerising, car park height limits etc.
I know the 40g is a beast. My existing set up uses a RAM mount (see pics below). Would i be able to fabricate the ball end to the antenna and would that support the weight?
Second and probably most important question- in the roof up position the angle is 45 degrees from horizontal. Would that be an issue for any antenna (whether dome or cylindrical-type) given the horizontal/ vertical elements ?
Thanks for any assistance
Phil