2011 iMac 27" - OCLP - Hardware Upgrades - Will it Still Work?

iMac 2011 27"
Intel XEON E3-1275 SR00P 3.40 GHz
NVIDIA Quadro K4100M
OCLP

Will my iMac explode? Will my brain melt? Or will it all be hunky-dory?

I want to do this soon. The iMac currently does not boot, as the stock GPU is quite dead. AFAIK, everything else works fine. I am replacing the dead GPU and decided to try one of the Xeon 1275 CPUs at the same time. Already have an SSD along with the stock 1 TB HDD.

I am watching Curtis Gross' YT vids. I know about the modifications needed to fit the 4100 in its bracket. Anything else I need to know?

Now, AFTER all this fun stuff, I want to run OCLP. With all this nonsense hidden behind my monitor, will OCLP see all my upgrades and changes to the hardware? Will swapping out my CPU/GPU like this break the patcher? I really want to use OCLP, so if what I bought on eBay is a problem, I will look for other chips or cards.

Lastly, if I get the machine running as planned and then manage to get OCLP to work, which version of the macOS ought I install? I keep reading that Sonoma and Sequoia are too intensive for this 2011, but then I read that the Kepler card is Metal, so it should be fine with Sequoia. This is because I am stupid and actually read the Google AI suggestions.

Can anyone here confirm that these upgrades will work, and if so, will OCLP still work after I have installed them? And of course, will Sequoia be a bowser on this 2011 machine after the upgrades? I am doing so much that it feels like the next thing will require the use of Scotch tape and Elmer's glue…

TIA!