Anyone have a few pictures of the proper / best place to mount the electric oil & water sending units on a 1992 300 4.9L motor? Thanks in advance.

 

I don't think they changed much throughout the years, but the stock location for the sending units for your gauges is:

Temperature:
You can see it right below the #6 intake port in the very back/left


Oil:
The silver canister in the far back behind the oil filter port.



There was also another temperature sensor in the thermostat housing that was used for the computer.

 

AB ---- Thanks for the pictures of the sending unit location. After I looked at them I went out to check my block and found the water temp sending still in the place you showed, I had painted over it and did not know witch unit it was.

In the enclosed image picture of my block it shows the upper threaded hole to right of the oil filter and just below the top of the block, that is for the oil sending unit, correct? Is the other hole just to the right of the oil filter for the oil dip stick?

 

Glad to help.
With your temp sending unit, unless you want to be sure it's new, you can probably just clean of the threads and away you go.

As for the oil, the one directly to the right of the oil filter port that's pointed upward is for the dipstick tube. The upper one RIGHT underneath the pushrod cover is for the oil sending unit.

 

AB --- Thanks again for your help. As for the stock temp sending unit I am not sure it will work with my S&W electric temp gauge that is on my motor run stand? I am not up on sending units, may need a S&W sending unit for their gauge. What say?

 

That part I have no idea about, you'd probably need to contact S&W about it. It might work, depending on what voltage range they use.

The temp sending unit converts temperature into voltage (like the oil converts pressure into voltage), with something like a range of 0 - 5 volts (I'm making that up for an example), with a range of 100 degrees to 300 degrees. So 100 might be 0 volts and 300 might be 5 volts. Operating temp (190) will be 2.25v which would put it at around 45% of the gauge.

IF the S&W gauge uses the same voltage range for their gauge as the stock gauge, it'll work just fine. But, if they use a different range like, say, a 12v range, then the stock gauge would just barely get the needle to move.
This can be dangerous if, say these voltage ranges I made up are correct, and the stock sending unit is putting out the voltage for 280° (overheating). This would be 90% of the stock gauge (way over toward the HOT), but on a 12v gauge would only read at 38%, which would look totally fine.

But, it's best to find out now while its dry, since the sending unit is below the coolant level and will dump coolant out of the engine if you remove it.

 

I will check with S&W on the stock water temp sending that is OEM. Really not a big deal in this total build project as the sending units are around $16 - 20 each. Thanks