I go with oil cooler,had the same on my mk1 Also when u change it the cooling system will need a damn good flushing out as the oil destroyed all the water hoses on mine, luckily its summer so u wont be loosing antifreeze when u drop the water I used washing detergent in mine!!liquid of course,stuck in run for a day dropped it out and flushed. Repeated a couple of times and all was well