Have a 1979 CJ5 that I'm rebuilding. Had my 304 rebuilt by a very reputable machine shop near me and installed the motor. Motor was a complete tear down and rebuilt. Comp cam, lifters, and timing gear, Edelbrock intake, Bulltear timing cover with HD standard oil filter adapter and HRC gears, Holley Sniper EFI with Hyperspark ignition. Finally got to start the motor last week. Had no mechanical issues except for a gauge issue for oil pressure. After that was resolved was able to do a break in on the motor. Motor is running great, very healthy oil pressure and idles beautifully at about 700rpms. Have about 1-1.5 hours of run time on motor, bled out the brakes, power steering, and hydraulic clutch. Shut the motor off and then noticed a drip under the jeep.
It is dripping clean coolant out drivers side rear of motor. Appears to be between the last 2 cylinders, 5 and 7. I thought it was dripping from the freeze plug right in front of the oil dipstick but after looking further it appears to seeping out of the head gasket. It is a drip. The coolant and oil are both clean with no evidence of cross contamination. It only occurs when engine is warm and cooling system is pressurized.
I called my engine builder. Both him and his partner are in their 70s and one of them used to build and race AMC motors. He told me not to panic and to give it several heat cycles and it will likely seal itself up.

My question for those who may know is, Is this what I do? Any thoughts or suggestions? Would hate to have to pull motor apart. It runs great with no evidence of any head gasket compromise.

Thanks

Harold