Not sure about the part number for the CPS. I have one in the garage but I'm not at home right now. I didn't order the MB part, I think I got mine from AutohausAZ and just ensured it was the Bosch brand. If I remember right, it was around $45 shipped to my door.

As far as plugs go, I just changed mine this past weekend. Car is an SRT and has 90K on the original plugs. Several people on here have said they used the NGK Iridium plugs. I went with the Bosch iridium plugs. I did this for cost savings and I also have had good luck with Bosch products. The plugs were $7 each from AutoZone and they offer a $2 rebate per plug - so the set of 12 is only $60. Since these are supposed to last somewhere in the area of 75K to 100K (the iridiums), I won't be able to report on the durability for about 8 years.

Good luck!

RL