Ford Repair: Ford 460 spark but no start, ford 460, ford f250

Question
I have a 1980 Ford F250 with a 1980's 460 in it -- went from running rough, to better after I advanced the timing, to hard to start the next day, to not starting the following day.  Good compression, rotor turns immediately when crank is turned, spark all the way around, new sparkplugs, cap, rotor, has MSD elec. igntion that is sparking, magnetic pickup trigger checks out good, I've looked at the gear on the bottom of the distributor, and it's fine... one question I have is if I put the distributor to back right to tdc and rotor to #1, but fairly sure I did... I changed out the carburetor to a different carb -- and after changing it started at first, but ran terrible, as if on 4 cylinders, but later quit starting once again.  I am practically at my wits end (which may not take that long to get to...).  Any help would be really great!

Mark

Answer
if you got dist back on one-and you have good spark at plugs-then that only leaves fuel delivery or timing-hold accel all the way down while trying to start in case flooded-you may pull a couple of plugs out to make sure they aren't satuarated with gas-it that all checks good don't rule out jumped time.