I just bought an e30 because I crashed my last one

. I bought the car with an 88' 7 series engine already in the car. I have been working out the kinks (as you can see the "mcgyver'd" air filter) but I am still having heat problems. The engine is supposed to have an oil cooler but it has been looped back via the blue hose in the pic. I have had no luck finding a replacement and wondering if anyone had any ideas or knew rough dimensions as I don't have much room left to work with. The car runs good for now and loves the highway but stop and go traffic makes it heat up. I should be fine for the cooler months ahead but any advise or tips is appreciated.