Hello, I need to help a friend reseal his M104 on his 1995 E320 for oil leaks and a bad head gasket. I've worked on M103s and feel very comfortable around that motor, but this is my first time doing an M104 and had some questions.

Here are my parts list that I have gathered thus far:

104 010 3720 – Head gasket kit
104 010 2130 – Valve cover gasket kit
003 159 6703 – Spark plugs x6
104 990 0012 – Cylinder head bolt x14
102 016 0376 – Cylinder head bolt washer x14

I am wondering if I am missing anything else?

Is it necessary to replace the timing chain tensioner and guide(s)?

I always sent my M103 cylinder heads to get the valve stem seals replaced, should I do this too on the M104?

Any other gaskets I should replace while I am at it?

Thanks in advanced.