If you're interested in having a permanent option for your oil cooler conversion these may be what you're after. while not our preferred method, we do get a lot or request for these and want to make it as simple as possible to fit for you.
In full transparency, we don't believe that welding to the almost 20 year old cast aluminum housings is a good idea. There are difficulties in cleaning the old metal and porosity may be a challenge you have to deal with. This is more of something you will have to consult your fabricator if they are willing to take it on.