3.0L oil and coolant temperature senders for the instrument cluster gauges/lights?

[jangell]

I have a couple of question about the 3.0L oil and coolant temperature senders that drive the instrument cluster gauges and lights. I'm working on hooking my new harness up in the engine bay, but I'm not quite sure what to make of these senders.

First, the coolant temperature sensor at the water pump is fine -- that easily hooked up on the harness for MegaSquirt, so no problem there.

The coolant temperature sender for the temperature gauge in the instrument cluster is the one I'm curious about. This is located on the cylinder head near the throttle near firewall. My harness from Josh (thanks again, Josh!) has a simple ring-style connector, but the sender appears to have two blade-style connections that are clearly meant for a plug (I think a Bosch-style connector, like the 2.8L CPR used?). I'm wondering if I can just attach one of the pins to ground and the other to the sender wire, on the sender operates like a resistor like the other ones do. I presume the 2.8L one was grounded to the engine, since it only had one wire.

Next, the oil senders. I had expected DeLorean-style senders were present on the passenger and driver's sides, but that doesn't appear to be the case. Instead, I found this:
- On the passenger side I have a large brass plug next to the oil filter instead of a sender. This is where I realized I should have done more research before now; for the most part I've been figuring out each step as I go along so that I don't get overwhelmed, and it's been working so far...
- On the driver side, there is what I think is the oil pressure sender near the main pulley end of the engine. Page 40 figure 100 of the 3.0L Engine Overhaul manual suggests that t's the oil pressure sender anyway. It seems to have only one (slightly bent) pin, and the docs say it acts as a variable resistor, so that seems like it should work. I'm just not sure what kind of connector it has, so I'm not sure what to get for my harness.
- On the driver side near the bottom of the engine is another sender with a two pin Bosch-style connector. I think this is the knock sensor, given the diagram in the Volvo Service Manual page 9-17 figure 13.
- Figure 13 also references an oil sender switch connector, but I don't actually see where the sender itself is when looking under the car, but I may just not be looking back far enough.

Also, it looks like I'll need a source for Bosch-style connectors, and whatever kind of connector is on the other sender.

I guess I could put the 2.8L senders in the 3.0L engine (I think I have them around somewhere...), assuming they fit, but it seems like the existing senders would probably be usable as-is... right?

I also realize that all of these particular senders are "optional", in that they just drive the instrument cluster, and aren't required for the operation of the vehicle. However, it seems like with a newly-installed engine, I'll want all the sensors I can get to make sure I didn't screw anything up.

Pictures attached. Thanks!