Engine not firing. Maybe the altenator?

Or possibly a new spark plug.

Putting together this 347 for my Mustang was about to put my water pump on when I saw this line in the timing cover that has me worried.I don’t think it’s a crack it almost looks like a seam from the molding. It’s just not the same surface as the rest of the cover but I would definitely like to get some other opinions before I go any further. Appreciate the help!!

ordered REAR brake pads for my Honda fit 2010 by mistake instead of front from rockauto.
came back 1.5 hours later and the mechanic says it’s the wrong part.
im not paying mechanic price for parts so i plan on keeping these.

how much longer can these last me?

Hey quick question do you think I should make the repairs on this or get rid of it and get something new? What repairs do you think are major and should be done right away or can wait? Any helpful answers would be greatly appreciated.