Shown in the center of the picture below is the furthest 4-way retainer towards the rear of the vehicle

BMW M52TU/M54 engines

Mishimoto started from the ground up for their DCT cooler design

Just look for this banner on the wall

and it is a direct bolt-on fit for all 6-cylinder E30 models from 1988 to 1991

CSF Race-Spec Oil Cooler, BMW E9X M3 S65B40 Shown in the center ofThe CSF Race Spec Oil Cooler is a TIG welded oil cooler with a cast endtank. This is the most reliable and durable option for the E9X M3 market, offering a perfect fit without the need for shroud trimming. Designed and Developed in Collaboration with High Performance Supercharger System Manufacturer VF Engineering Drop in Fit Requiring No Modifications to Install Accepts All Attaching OEM Components Including Oil Line Connections, Mounting Brackets