16v cam timing marks

Didn't really know where to put this but i have been trying to put my cams back in and can't get the timing marks to line up??

I have not taken the sprocket off. all i have done is take them out as one and ground the valve seats,replaced the seals.
now trying to put them back in

Shall i take the sprocket off and replace the cams or shall i put them in with the sprocket on?

is there only one way the sprocket will fit on the cam?

also what are the red dots for?

Is there any special way to go about it? any help would be much appreciated

Cheers

Some pics

How they are is right fella. They should match up in line along the top of the head Andre mark on the cam maybe needs tweaking slightly clockwise but when tightening the cams it can twist so make sure and tighten each side equal.