You don't EVER need to "clearance" anything in there
If something is hitting something else, it's because something is wrong, bent, loose, worn.
Since you have the pump off, you can feel the chain "in there."
Read your service manual. There's a procedure in there to check the timing chain
"The quick way" is to pull the dist. cap and wrench the engine back/ forth until the rotor "doesn't quite move. You can FEEL the chain "against the slack". See how far the timing mark moves when you do this
By the way it 'd be pretty darn handy to know what you are working on. It's not "blue"