1971 CJ5 with believed to be original power train. Over the last couple of years as I have been working on it to get back as a weekend driver, encountered issues with parts not matching what it has vs. what the retailers suggest. Most recent - temperature gauge not working, pulled sensor from back passenger side of intake, ordered new one on RockAuto only to find it much smaller than what I pulled out? ACDELCO 2133199. I went to O'Reilly's last night and their system says BWD125 - again - much smaller. Any input / suggestions welcome.