I thought you said earlier you were going to put the sensor on the side of the block. Did you change your mind or did I read this wrong? I don't know what MPT is.

 

NPT is National Pipe Thread.Don't know what idiot's don't know it 'cause it's been a recogenized standard for 50 years.
Ya got the wrong sensor.Was it from the same place that didn't know NPT?
The sensor ya got may be metric don't know but ya can get the adaptor (1)fittings to plumb it up. Sounds like ya need to go to a fitting or hyd supply house or where they KNOW something about fittings and take the 1/8" and the sender and say "I need to put this here,like this, do ya have the fittings I need".

BTW a 5/16" SAE (fine thread) bolt will screw part way into a 1/8" NPT thread fitting.

 

Ok that is making more sense now... See I purchased the sensor at my local autozone and they said that the sensor was correct. They were only able to find a 5/16" elbow. He tried threading the sensor in and it went into the elbow as far as it would go by bottoming out. However, the male portion of the 5/16" threaded elbow was too big of a size in diameter to fit the engine block. So when you stated that the 1/8" NPT size would fit the block behind the intake I went to my local ACE hardware store and went down the Plumbing isle and found 1/8" MPT brass fittings. These looked way smaller than the 5/16" sensor threads and I was hoping this would thread into my block. But now my problem is that the 1/8" MPT brass fittings wont allow the 5/16" threaded sensor to thread into the female portion. So basically either the sensor is the wrong sensor or 1/8" NPT and 1/8" MPT are totally different sizes.

Thanks for all the help. I will figure out what to do tomorrow.

 

I am thinking MPT may stand for "metric pipe thread" there is also BST which is the British standard.
Take everything to a fitting supplier and let them get ya a fitting but make sure the sensor is the right one.Take the sensor to a NAPA store or a GOOD parts house and ask for one for your car and compare.Then see if it's 1/8"NPT or some metric size 'cause ya won't find a NTP thread on one end and a metric on the other end of the "L".
We have a fitting supplier here that does fittings and hoses and ya can find anything that is or was ever made in the fitting line or hose line for all 3 standards.If they don't have it they will get it and it isn't often they have to get it. I think ya are going to find the sensor is wrong.

The block being 1/8"NPT (I know that's correct)I don't see it being a metric sensor or GM has a special fitting for it(made special for that) but I can't see that either.