I ordered a new heater core but when I got it it was totally too big. I ended up ordering up a new one that is supposed to be for a rig that has rear heating even though mine does not. I had put extra foam padding on the heater core because this one iss a little bit smaller that my original one. The tubes that were originally on mine I had to reuse and put on the new one, before I put the dash all back together I fire up the engine to see if the tubes leaked and they didn't so I put the dash back together. Now one day later and my carpet on the passenger side is soaking wet again with antifreeze. Does anyone have advice on how to get the 4 runner heater cores to seal up?