If any one is looking for a lower temperature thermostat for a standard LS3 6.2 this is what I found and fitted, and it works great.
I have removed the 86deg stock thermostat and fitted a 76deg full flow racing thermostat
My AK set up use to run around the 95 to 105 temp range, which I hated, yes the LS motor is designed to run hot, but it just did not feel right to me. It does get measured in 2 places, 1 via the Canems ECU which also controls the fan set point on and off. Temp sender is in the P/s cylinder head. OEM type.
The other is a sender in a fitting in the D/S cylinder head to my temperature gauge Smiths flight type. Which I removed and blanked off, I have the sender in the top Stainless hose connector now, direct in the water flow, and could use a fan controller if you wanted to fit that in line.
After a bit of searching around, I found there are possibly 3 different type of water pump and housing fitted.
I thought I had found the correct one online at 71 deg, ordered it, and its way to small so returned it
that's when I found the below video that shows how to measure which size you have.
I then spoke to Mishmoto and they advised to me go with this one.
There are plenty of options in the USA sumit, Jegs etc, but with shipping and tax I gave it a miss.
https://www.mishimoto.com/chevrolet-corvette-c6-racing-thermostat-09-13.html
Its not cheap but well worth the investment and peace of mind, even in the last heat wave it never went over 93
Perfect fit, same size all round, but what a difference its made, my LS3 now runs all day long hot or cold weather at a steady 80 to 93 ish, not once has gone up to the 100 or just over.
I Hope this helps other LS owners.
Sorry still cant work out how to post photos quick
LS thermostat size chart.JPG