Took me a little while to find it. Go up to the top of the main forums page, there is another 7.3 section there, too many threads to list, I saw another one about diagnosing oil leaks.
I think his user name is Marty now, sorry!
One thing occurred to me, I might be wrong, but I don't think injector orings cause high oil use for long, when an oil ring blows, it will usually push ALOT of oil into the fuel system (oil pressure is way higher than the fuel pressure at the injector) so it will push a gallon or 2 into the fuel, did you pull your filter and check it for motor oil? If it's clean, I'd look elsewhere because the fuel ports are below the oil ports, so oil can't get into the cylinder without going past the fuel ports. I lost an oring once, got a little smoke, but the first clue I had was it started missing and then quit, I checked the oil and was 2 gal low, filled it up, ran fine, 15 miles later I was 2 gal low and on the side of the road again. Checked the fuel filter, it was more oil than fuel in the bowl.
It could be an oring, but I'd advise a little more troubleshooting before you spend $100 and a day or 2 on something that might not be your problem. Also, if you are going to replace orings, might as well do glowplugs while it's apart, and ford has a kit for the under valve cover ("UVC") harness, it's about $18, helps cure the problem of loose connections. Actually, there are a few more things that can be done all at once, Tymar intake, EBPV delete, CCV mod, foil delete in the charge air pipe. You'll be taking all that stuff off anyhow, why do it again later?
99 F350 CC DRW 4x4 PSD 6 spd 4:10 Programmed, 4"exh, 8" lift Kelderman 4 link air ride rear, southbend clutch (and arm!) 295/85R22.5's, AFE stgII gauges, push bar, 07 lights, recon smoked fender and rears, ARE shell, DynaTrak combo front,
, Short throw Shifter, Airdog, Regulated Return fuel, Coolant filter, Bypass Oil Filter. Next:BB Turbo, CAC, Injectors, HPOP, Head studs, and anything else I can afford