coolant leaking from tube that goes from engine to heater

hi
i have a 91 d 50 2.4 and the metal tube is leaking that take coolant down the side and around back of the motor to the heater core.
I believe there must be a o ring where the tube slides in.
I have not taken it apart yet, hoping to have all parts needed before taking it apart.
it appears that one bolt and the tube will slide to the rear and access will be gained to the oring( i assume ).
the parts store is no help, and they want to try and match one up after i get it apart, assuming it is in one piece.

I am hoping that someone can give me a part number, and verify my guess about the oring. I never have had any luck trying to match up orings, it seems if i get the id correct then the od is wrong.
so i am hoping to avoid the multiple trip game to the parts store.
please help
thanks

partsbase.org FTW!

we do have the caps program you can download and get the part number you need.
http://www.mightyram50.net/vbulletin...e-Tech-Section

i tried partsbase.org.

could not find the mighty max

i downloaded the caps program , but it will not work with operating systems after xp, so i am unable to use it.
I hope someone can help me find the information i need.
thanks

http://www.factorychryslerparts.com/...driveLine=7050

close, but i have the 2.4l engine and the pic does not show quite all of the way to the connection spot i need
the pic you show is for the 2.0

Try partsbase.org again, it's called the Mitsubishi Truck. You'll have to spend some time drilling down but it's there. Has all the same fiche as CAPS.

The O-Ring comes with the Waterpipe. Best thing is to just remove the waterpipe and go find the right size O-Ring