Seems like there was this long thread about oil coolers a while back, Wow. 850.00 bucks for the in-frame kit. Aaaarrgghhh !
For one, the price, Segundo, what's in the frame tubes : hmmm, drilling slivers, welding slag, cigarette butt, who knows? And keep in mind cooler is not always better. Engines need a measure of heat to operate correctly. Any temps south of 165 or so is not efficient.