Before ya'll get too into this, make sure that the sensor works the way you think cause I'm pretty sure it's not that simple...... most oil level sensor I've seen are capacitance type, meaning you need an external chip to do the logic routine and operate a relay. The sensor on it's own is useless. It's also going to be somewhat sensitive to gunk, wear, and variation in oil type. Not saying it wouldn't work, but there's more than meets the eye.
This why I want to use a simple float switch.
The low coolant light was an ISSPRO kit, let me see if I can find the info..... had to solder a bung into the radiator top tank and do some wiring but it works well. Okay, found it - ISSPRO 4290. Quite expensive though - $161 was the cheapest I saw in 30 seconds of looking. I feel like I got mine for under $100 though.... not sure if the price went up or what.
I'm also looking at installing low oil level sensors for the trans, t-case and rear but haven't figured out exactly how yet. Long range plan is also to setup oil temp gauges and warnings for those 3 as well.... I plan to have a master caution and then a small board of various warning lights. Looking at a oil cooler for the trans and engine oil too down the road.
I think you're going to work harder trying to put a bung on the pan in the truck than just biting the bullet and pulling the pan......