top of the block question!

hey all!!

ok, so out changing the thermostat and noticed 2 things. What is this open hole in the block for? Looks like a cap could screw in there?



and also, this toward the front of the block and just to the side of the thermostat housing, it appears to be a plug into the top of the block, a brown wire coming off and into a cluster of wires, excuse the foil and birds nest in the above pic, I intend to clean that up, eeash!



thanks in advance everyone!

Hami

The first hole is also visible in the second picture, and appears to be a blind hole. Probably a mounting point for a bracket, my guess would be for an A/C rear bracket. There will be others like this at the rear, for the coil mount.
The second one is the opening for the temp gauge sending unit. It goes into the crossover for the coolant below the thermostat.
Both of these are actually in the intake manifold, not the block.
There are also wire clips on the right side valve cover. The wiring for the temp gauge and the alt are in a loom that goes in those.
Here's a pic of mine BEFORE....

aha! makes total sense Rod! I had a feeling that was temp but wanted to confirm. And yes, manifold, not block! Oops! thanks for the info!!

and remember the wire from the tempature sending unit is a resistance wire.so don't cut into it or throw it away.

nope, no cutting, it works!

if anything, I thought of reinforcing it. It appears to be weak from being moved around and might need a little electrical tape where it connects in to the sending unit.