Has any one done anything to improve the water cooling in their VR6?

My cluster died and was replaced with another one, however when the temp was sitting perfectly on 90 with the old one, the new(er) one would only sit on 70ish. I figured it was just a bum part and didn't think much of it. After doing a track day yesterday it didn't get over 90 and at the thermo's didn't stay on for as long as I thought they would.

So I'm eyeing off a new set of all temp sensors, these ones:


I'm also considering a new thermostat.

The sensors are easy to replace, if somewhat fiddly to get at, but whats it like to do the thermostat? I also have a new temp sensor to replace the one on the radiator, although that one really looks painful to get out unless you remove the radiator, something I wouldn't mind avoiding if possible.


The old cluster seems to have been an older model with lots of caps and a flat face:



The new one has IC's and a slightly different face:



It also does 20 - 260 where the old one does 0 - 260.

The Rev counter, speedo and fuel guages are just right, the lights seem to work right. But I do wonder if these two cluster types are 100% swappable?

The sensors are cheap at ~$100 for the lot including new O rings and clips, and being that the originals are 12 years old it's not a terrible thing to swap them out. On the flip side, the engine runs perfectly as it is.

Ah the world of the VR6, nothing but fun!