You might be able to add the egt sensor then wire with a double pole double throw switch. Then you could switch from H20 to EGT but not read both at the same time.
If you do that – make certain you have an impedance path that is very low. (good switch). Or even better, test the temp sensor in boiling water to make sure you haven’t changed it’s response due to the increased resistance.
i mean, my only real reason for wanting a egt is so I know if i’m leaning out too much, which is mostly why I want to be stingy about this whole ordeal