[V8] Broken distributor cap

[QuickAudi at aol.com]

Ok, here's why I asked about the distributor caps/rotors.  I had the power steering rack R&R'ed last week; picked her up Saturday morning.  Rack isn't leaking, which is good (thanks Jorgen.)  Drive about ten miles, stop, open hood, have a new p/s leak.  This one is from the pump, hence the pump questions.  The further I drive (had to run beyond Nashville to get the new tires put on and the alignment done), the worse the car ran.  Acceleration was a little balky at first, then got to be like a horrible surge.  Got the tires/alignment done, and started immediately for home (160 miles away.)  About ten miles into the drive, pulled over, left the car running, popped the hood.  Left distributor cap was jumping up and down like it was on a trampoline.  Saw a crack in the orange part of the cap (the underneath part.)  Used zip ties to keep it kinda close to on, then limped home, literally.  Last 70 or so miles felt like a four cylinder pulling a two ton car.  I am going to take it back to the shop to get the distributor cap replaced.  FYI, had to take the broken cap off to see which type of rotors I have (got the push-on type.)
Here come the questions: I'm going to trailer it there.  Should I even attempt to start it?  The cap won't do any good, so I could unplug the wire to the cap so it wouldn't try to send any spark.  Should I unplug the injectors if I do that?  Flooding the engine on one side wouldn't be good.  
How much damage have I done to the engine so far?  What else should I look for that might have been broken by me driving it in the current condition?  
Also, the inside (orange) part of the cap had a lot of pieces missing.  I found a few, but it seems like there should be a bunch more.  Two explanations: one, they were broken out and he just put it back on anyway; two, maybe there cap saw so much wild spark that it burned them up?  I'm sure #2 isn't possible, but maybe it is?  I've heard of weirder...


Thanks in advance for all the help 
Joel
'90 V8q (hurtin')
'86 5kcstq (passin' everything on the road)