Right angle oil filter adapter

The original plate that was there needs to come out. The original screw on filter holder has a 3/8 square drive that comes out with a 3/8 extension. The plate is held in by that, may take a little prying to break the seal loose. If you noticed the surface area is recessed and the angle adapter sits down flush on that with the large gasket then the bolt goes on with it's fiber gasket. As stated before, make sure it's clean.....been running one for two years with no issues. Yes it's the aluminum after market type. I would think you have some serious flow/pressure issues with the plate and adapter in there, What is your pressure at idle and driving?