The thrust washer goes between the sprocket and the tower. It has a notch that should line up with the line on the top of the cam tower. Lining it up is sort of a moot point, since you have bent valves.

On the 380 and 420 that I have repaired, no damage was done to the pistons. But you won't know until you get your head off.

You have the rest basically right. You need to replace the three rails in the heads, the plastic bits in the cam oilers, the timing chain, and the tensioner. As I recall the machine shop bill for the head was about $500, but they were able to supply four used exhaust valves. I think that the other parts and gaskets were about $350. I also dropped the pan and cleaned out some plastic pieces.

The alternative is a used head, but that is a crapshoot. All that is guaranteed is that it is "rebuildable." A used engine is another alternative. Make sure the cams are good, as they are expensive, and you would have to do the rockers as well.

The job is a lot of work, but nothing complicated. I think that the book for R/R one head is 17.5 hours. Be sure you have #1 at TDC before you unhook the chain, and good luck.

__________________
Chuck Taylor
Falls Church VA
'66 200, '66 230SL, '96 SL500. Sold: '81 380SL, '86 300E, '72 250C, '95 C220, 3 '84 280SL's '90 420SEL, '72 280SE, '73 280C, '78 280SE, '70 280SL, '77 450SL, '85 380SL, '87 560SL, '85 380SL, '72 350SL, '96 S500 Coupe