You would have to add gallons per tank before you got close to adding too much. A 7.3 would probably run on the stuff - it runs on just about anything. The damage you are doing by adding more than the recommended amount is to your wallet.
2003 F-250 XLT Crew Cab 7.3L, Chrome BigTex Grille Guard, Quad pillar - 3 ISSPRO gauges (trans, pyro, boost) and DP-Tuner F6; Roush fuel pressure / temperature / oil pressure gauges, Ford Severe Duty AIS, 31 row 6.0 transmission cooler, ScanGauge II, Marinco mod, Walker BTM
"IF YOU CAN'T FIX IT WITH A HAMMER, YOU’VE GOT AN ELECTRICAL PROBLEM"