Get the double bearing idlers, they're much more reliable and live longer than single bearing. I have the Metcos and they come highly recommended from most Cobra owners. You can get them direct from Metco if needed: Cobra 5-Piece Idler Kit, : Metco Motorsports
The only thing that jumps out at me from that last log is the fuel pump duty cycle. You would think it should show 100% all the time with a return fuel system?
Battery voltage looks good, MAF appears to be working. Only other parameter I'd like to see is "pressure drop across injectors", see...
Stock alternator and tensioner? A lot of belt squeak issues are caused by pulley misalignment. They make a laser tool for checking this but you can use some 1/2" wide flat iron as a straight edge across the crank pulley to get an idea if one of them is not aligned.