I recently purchased an M1 intake for my small block and for the life of me cant figure a\out where to put the mechanical temp sensor for my gauge,I am having a sever brain fart
I just went through this problem. A member here suggested going to the local hardware shop and get the proper brass fittings to make a "T". This allows the heater hose to go in the top and the temp sensor to go in the side. Just make sure the temp sensor doesn't bottom out. This setup worked perfect and looks good to. The fittings should all be NPT threads. My digital camara is on the blink right now otherwise I would post a pic for you. It is a lot cheaper to do it this way and you don't run the risk of breaking the intake in any way.
Same as above, but i had a bung welded and tapped one for the temp sender and one for heater hose. worked fine. Sold intake for 100 bucks last year,at a swap meet.