(1) Adsitco: I have no personal experience with them, but for some reason my restorer had LOTS of trouble with them over the years, and wouldn't use them. Maybe this was a fluke; perhaps others on the list have purchased from them and had good experiences?
(2) injection pump pipes/plumbing: for a load of parts like this to be plated, you are looking at about $200. Try Burbank Plating (search for the thread on CAD plating) or Prime Plaing, both in California for true cadmium plating. CAD plating leaves a bright silver finish, and then they typically give a phosphate wash which gives the gold color that we are all familiar with. If you are hesitant about sending out your parts, as many seem to be, you can find a local zinc plater and get the "ersatz" CAD plating which is a iridite or phosphate wash over zinc. Hi grade steel nuts and bolts often have this finish.
(3) Do you just paint, polish, or powder coat various engine bay components? It depends on the part. The injection lines are CAD plated as we've noted. Any part that is typically painted can be powder coated in the exact color IF it can handle the oven baking. I'm a firm believer in powder coating, it lasts a lot longer and provides a harder finish. Metal polish and buffing go a long way in restoring finishes. Get yourself an Eastwood catalog.
(4) The car runs strongly, while the engine is would it be wise to have the clutch changed out? Any other things to do with the engine out? Oh, yeah...if you have the time and money, all wear items and anything rubber should be replaced. Rebuild the clutch, the tranny, etc. Remember it is a good 8-12 hours of labor to remove this stuff, so while you have it out and have access is the time to do this work. Case in point: Main transmission seal on an automatic is a $5 part. It will cost $500 to replace it with the labor. Get it?
(5) The car is medium bllue with black hartop and wheel centers. It was originally light beige and black, I believe from the data plate in the engine (181 and 040). I do like the medium blue and have decided to repaint it in the same colors that it is presently. Is this wrong? I feel that I would not like light beige. Your choice of course. Correctness and originality are for resale and concours. If you don't intend on showing or selling, but rather enjoying you should have what you want.
Michael Salemi
1969 280SL
Signal Red w/Black Leather
Restored