SLK no start.
 

This morning my 98 SLK 230 would not start.. Checked Ignition spark first and it was good. Then Checked for fuel pressure at Schreader valve on fuel rail. No fuel.. Before I went to connect fuel pressure gauge, which seemed like it would do no good, since there was no fuel coming out of valve, static or cranking while depressing valve. I went over to the fuse box located in engine compartment on driver side, front of firewall.. Reason for that, was more a hunch, since I have had a few (several) problems in that area with radio failure, and some other componentry problems... I bought car used and had to fix several sloppy slice jobs in wiring loom under that fuse panel.. I had previously removed all fuses cleaned and applied dielectric grease, soldered and used shrink tube on aformentioned bad slices.
After the movement of the fuse panel the car started. I did nothing specific just looked (touched) at fuses and maybe moved box a little.. Its been starting harder (cranking longer) than usual now thoughout the day. I have watched this forum for awhile and have been impressed with the knowledge here. ( I have to say right now I have a serious M.B. dealership allergy) so here are a few of my questions.. If you will indulge me?
1. Which publication has the best specific wiring diagrams for mercedes? i.e. Mitchell, Hayes, or maybe even subscribing to Alldata..
2. Any SlK owners have problems with that fuse panel?
3. Where is K40 relay board? Does it have any fuel relays/functions involved with it?
4. Where is fuel pump relay?
5. Is there a oil pressure switch that has to be satisfied to enable power to fuel pump/relay?
6. If DAS system fails I assume car will not crank. or does it just loose fuel?
I am sure everyone is thinking fuel pump, as I am trying not to. Because, I have had GREAT service out of bosch fuel pumps, but I will perform the routine tests.. Car only has 71,000 miles on it and I feel its not the pump.