This post has turned out to be very informative so I thought I would post the UIM LIM how to on gaskets replacement that I read from Dan.
https://www.gmforum.com/mechanical-1...ts-l36-297702/
If there are any others please post em ...

Here is the FelPRO kit you want.

Amazon also now carries the aluminum elbows.

I know you will have to get them from your area, just posting links to those in case others need to order the parts, RockAuto also sells them of course, I just deal with Amazon since I have a Prime account, and I get 2 day shipping free.

Here is the link to when I did my UIM/LIM, I had never done this before at that point, so the thread should e helpful to others that are new to doing this, if there was a question rest assured I asked it, lol
http://www.3800pro.com/forum/intake/...im-gasket.html

Just got done doing the upper and lower intakes, bought the car last month for 750 so far new water pump, upper manifold thought I'd do it with the ATP, and lower with the Felpro MS98014T gaskets, new Dorman aluminium elbow, after the plastic one leaked. ATP kit came with everything including injector o rings,all this done and no leaks now I have running hot problems seems like fans should be coming on gets to around 230 and nothing, I turn on the AC to max and they don't come on right away, anybody got any ideas ? Don't need it overheating after all this, and shouldn't they also come on with the defrost ? This thing needs more work, but looks good for having 215,000 miles also has check engine light on and off. Still have to look into that issue. Any help would sure make things easier gettin tired of brainstorming already.

if they both come on at all, then the computer control and relays should be good, maybe the temp sensor is sending the pcm the wrong reading