Connecting two 8K UP3218K to single video card

I know it's gluttonous, but I'm enjoying using two of Dell's 8K UP3218K monitors at the same time on my main PC. This allows for maximum information viewing in multiple windows at Retina resolution, close at hand, in perfect clarity without a pixel in sight.

However, in order to do this, I have to use two GPUs, since each only has three DisplayPort connectors (i.e., since each 8K monitor requires two DisplayPort connections for 7680x4320 60Hz, each GPU can only support one such monitor). Doing so eats up so many PCIe lanes on my motherboard that I cannot concurrently use its 10GB Ethernet port and a fast PCIe NVMe SSD.  It seems that I could resolve this issue if there were a way to connect both UP3218K to one GPU, which would require using an adapter for the GPU's HDMI connector as a stand-in for a DisplayPort. However, current offerings (as of September 2022) in the HDMI-to-DisplayPort adapter arena are limited to 4K 30Hz. To clarify, each DisplayPort line - if it is to carry half the information necessary for an 8K resolution at 60Hz - must input two times 4K information at 60Hz to work properly with this monitor. 8K is four times the resolution of 4K, not two times.

Does anyone know of a better HDMI-to-DisplayPort adapter on its way to market, or know of another workaround?

Thanks in advance.