Mbe 4000 problem

Working on a MBE4000. Had a wrist pin bearing fail. Replaced the pistons, rod, liner, and head. The liner i got for it had a groove for an o-ring just below the counterbore. Prodemand manual said that is the new style liner and needed the block cut for the oring. Local freightliner dealer had no idea about any of it. Put the liner in with oring and it wouldnt seat. Put it in without the oring and put it all together. Head gasket was same as the old one. New head has a ridge where the fire ring sits, cant remember if old head had that ridge or not. Head was torqued per manual. Went to fill with coolant and found a big coolant leak at the front of the head right in the middle between the head and gasket. Took it all apart and cant see any reason why it was leaking there. Any help??