Did you ever get around to your intake-manifold-removal project? If so, did you take a closer look at the EGR temperature sensor?

I bought a complete used intake manifold and will doing all porting, polishing, gasket matching and switch-over modifications on it while on the bench. That way I'm not pressed for time or in any rush to get it back on my car so I can drive it. But I get to live with that infernal "insufficient exhaust gas recirculation" CEL until I get it done. I'll announce it soon as work commences on it.

if due to any number of unforeseen eventualities it appears to be a better-suited process for it. Time will tell.