Leaking exhaust from pass rear corner of head

[madprof01]

Evening Everyone,
I have a customer who owns a 94 7.3L F-250. Truck runs great, after I stopped some major oil and fuel leaks as well as got it boost again, firing on all cylinders. My customer could not be happier seeing how how he has burned through $6000 without any one repair lasting more than three weeks.
TO the point! I 80% sure that this passenger head, at the rear inside corner is leaking exhaust gas, and now spitting oil as well.
My question is has anyone seen this before is this a plausable issue or am I just not seeing the real leak? If this is the case is the head cracked or my thought is a bad head gasket. Knowing that head gaskets do not fail on this engine very often.
My recent resealing adventure included: HPOP, Fuel filter housing, Turbo ped., Rear Oil Galley plug, both exhaust manifolds gaskets, downpipe seals, collector gaskets, and I have new valve cover gaskets with harnesses that i have not installed due to not having decided to replace injectors or not.
Any insight would be greatly appreciated!
Thank you
Eric

[alberta 7.3]

The large plugs at the ends of the HPO rails can leak, which would be in that vicinity. As far as the exhaust leak, that makes no sense with all the stuff you've done. Sometimes the bolts in the turbo exhaust housing can come loose and fall out. I'd say pressurize the exhaust with the truck off and start listening for the hissing.

[madprof01]

Good idea! in fact as I am learning the idiosyncrasy of the IH engines. I am finding that is a very useful and easy test! I will do that today and let you know what I find.
I did just replace that plug and the oil that is there is splattered as if it was propelled by the exhaust. I am wondering if the turbo is the culprit all along. It was boosting when took on this project. So im sure its pretty coked up. and returning to operation would show issues not discovered previously.
Thank your time. I will post my findings.
Eric