What is this (shinny silver) 1st picture? Drivers right, lower front of block.

When I was disconnecting wires this plastic grey cap came off the "What is this" very easy. The wire and it's connector underneath doesn't make sense to me as to how or where it connects.

http://i94.photobucket.com/albums/l1...Whatisthis.jpg
http://i94.photobucket.com/albums/l1...Whatisthis.jpg

Oil pressure sender unit.

Thanks Bill.
How the heck does that wire connect?

It slides on.

Another question...when using ARP studs and nuts, should I put the studs in then somehow gently lower the head on? Or, what's the opinions and experiences from those who have installed these ARP's?

Thanks...I can see that now.

Another note for anybody...this EGR cooler area I now know has been the root cause of several problems for me and now the main reason I will do all my own work on this car.
1) The first and only BHG I had was 'repaired' by an ex-Longo Toyota mechanic. As the EGR inspection and subsequent new EGR gasket is not a required process to just replace the BHG, and the EGR cooler cover-plate gasket is not even included in the head hasket kit, this apparently was never touched. This is insane since you can not get to this EGR cooler properly without removing the head. Shortly after I got my car back I started having a moderate exhaust leak in and around the back portion of my manifold.
2) I hired a different "mechanic" to heli-coil the bolts as they had streched and when I told the first "mechanic" he said "yes, that is a problem with these cars". (why didn't he suggest replacing those bolts during the BHG job?)
After this second mechanic heli-coiled and semi-repaired the exhaust leak I could still detect a leak from the EGR area. I tried and bought many funky tools to try and reach the bolts but couldn't get to them all.
This leak got so bad the heat burned up my speedo cable covering and broke the cable. (twice)
3) I hired a 3rd "mechanic" who said he could do it without removing the head. His shop seems to have Ferraris, MB's and other high end cars there so I let him try. It seemed to be OK for a few thousand miles then apparently started leaking fluid. (That would seem impossible unless I had another BHG).

This is when I decided to do my own work.
I now have the head off. Took the EGR cover off and noticed 1st the bolds did not all seem tight. Then upon visual inspection of the cover I could easily see the surface was almost warped looking, enough that no way could you get a good seal. I also noticed an eroded area and pin-holes on the inside elbow of the heater hose from the union. I'm pretty sure this was the fluid leaking on top of the EGR cover, bubbling from the actual exhaust leak through the EGR gasket, giving the elusion I had fluid leaking from my EGR. (no sign of fluid ever being inside the EGR cover)

I just had my head machined and also had the EGR cover machined, along with the exhaust minifold.

Moral of the story...make sure you deal with this stupid EGR issue whenever you have your head off...

AND...do your own work if you want it done correct. Three "mechanics", lots of down time and my personal man hours just taking the car back and forth to these loosers, several thoudand dollars, and they ALL missed or mis-handled this EGR problem.

I agree totally. Do it right, do it once. And do it yourself.

As far as the ARP's, I'm a big fan of ARP bolts. Ease of installation with ARP's unsurpassed quality. And unless you are running over 500whp, I don't think ARP studs are needed. Unless you like juggling studs, washers AND nuts all covered in ARP moly lube. I prefer to juggle just bolts and washers. Plus its a tight fit inbetween the lifter bore castings for ARP bolts but it IS possible without machining the castings. I've "HEARD" that studs DO fit without removing the block from the engine bay but I've never used studs on a supra so I can not verify. I can only verify that bolts fit without any problems, it was actually fun installing the head bolts!!

So you're saying you have ARP bolts, not studs with seperate nuts?
I wasn't given a choice but maybe I can exchange the stud/nut set I have for just bolts. Would be much easier.

I would think by my last post, my sig and the picture in this thread of my ARP bolts that you would know what I used. Yes, I used ARP bolts.

No don't return the ARP studs. Since you already bought them, use them. They are indestructable. I now wish I used them just for the bragging rights lol. But hey, do you. It's your car.