First lets look at the oil filter housing. If you have the original that has not been modified you will be alright. If the housing was modified so the engine could run without the oil cooler you will have to find an un-modified original housing. You can tell if it was modified by looking to see if the oil cooler bypass valve is still there. The one in the picture has been removed. Also now is a good time to replace those old O-rings on the bottom of the oil filter housing.
Now that I have the correct oil filter housing I had to find the correct fittings to connect the hoses to the housing. I found the hose and fittings at a shop that carries Parker fittings. I had them make the hoses about 12" longer then I needed because I did not know the final location of the cooler. The hose fittings are Parker EXKW412.
I chose to use the B&M oiler cooler (Part number 70265) from Summit or Jegs. I liked the size of this because it looked like it would fit just to the right of the starter. The brackets were made from 1" by 1/8" flat bar that extended about 2 " below the cooler so I weld them to the cradle. During the test fit I figured out that I needed 1 90 deg (Part number 2PHC1/2CD90S) and 1 45 deg (Part number 2PHC1/2CD45S) fitting to go from the cooler to the hose.
Now that I have the parts that I need it is time to start the installation. First I mounted the oil filter housing to the block. The 2 O-rings that go between the filter housing and engine block can be found at your Caddy dealer if you want to install new ones. I connected the hoses to the filter housing and ran the hoses over the engine and down to where the cooler would be located.
Now I went under the car and placed the oil cooler in position and tack welded it to the cradle. Tighten down on the cooler fittings and aligned them to make a nice connection with the hoses from the filter housing. Remember to keep the hoses away from the exhaust piping and sharp edges. After making sure the hoses were in the position I wanted them in, I marked them so that I could take the hoses back to the hose shop and get the cooler end fitting crimped onto the hose. After I knew everything would fit I completed the welds on the brackets to the cradle.
Once the hoses were completed at the hose shop it was time to do the final assembly. Install the hoses in the filter housing finger tight. Now install the cooler ends and tighten the fittings. Next remove the hoses from the filter housing. Using a small funnel fill the hoses and cooler with your brand of oil, it will take about 3/4 of a quart. Place the fittings back in the filter housing and tighten. After starting the car, make sure you check for oil leaks at the cooler and the filter housing. Enjoy.