88 f350 missing and flooding out!

I bought an 88 f350 from a gentlemen who had just put a new 460 in it about 2 years ago and it has a little over 1000 miles on it. It was running great after i bypassed the fuel switcher because of it not allowing any fuel through it and I went out to start it up one morning and it just started missing on two cylinders all of a sudden and flooding out badly. I replaced the cap,rotor,wires, and spark plugs and it is missing very badly. The miss seems to be located on cylinders 4 and 5. I can get it started but it will die if I try to rev it up, it bellows black and blue and then dies in it's own cloud. :banghead: could this be a fuel pump problem? I think it only has one fuel pump on the frame rail, but I don't know how to tell if it has the other two without pulling the tanks down and looking. Any help would certainly be appreciated.

I done another compression test on the motor and found 3 cylinders with strange compression readings. On the first crank it got 145. I bled the compression gauge off and cranked it again and only got 4 to 5 psi. I decided to remove the oil cap over cyl 5 and found the rocker arm completely turned sideways. I took off the valve covers and found three bent push rods. My question is what causes this to happen. I put in new push rods and it now runs like brand new. Are these engine notorious for bending pushrods?

Someone probably put longer than stock push rods in thinking they could get more horsepower out of it without installing the correct rockers to go with them, once the rocker hits the end of its travel and the pushrod wants to push more either the rod gets bent, the rocker breaks or the rocker stud gets pulled out of its hole.