Not that it would be better than the sandwich adapter but you could always run it like how they run rear end coolers on some race cars. Weld two bungs into the oil pan, get a small electric pump, and pump the oil through a cooler and back into the pan. It would be easy to use an electronic thermo switch to turn the pump on and off, so it only runs when the temp is hot enough to need it. With a setup like this you wouldn't need to worry about the pressure loss due to the adapter, lines, and cooler that you get with a regular setup, since it is on a completely different circuit from the motors oiling system. The only problems I can see are you may need to add a few more baffles to the oil pan, and use some check valves in the hoses so when its not running the oil doesn't drain out of the lines and cooler. Since this would over fill your pan and could cause the pump to not operate correctly when it starts full of air.