Timing Chain lower sprocket bolt?nut

[McGD4]

I am tearing down a M50B25 engine and I cannot get the bolt/nut off of the
lower sprocket of the timing chain.
Also when I was removing the TDC wheel the thick round part behind it did not come out and I cannot get that out either.

How would I go about getting these 2 things off.
These are the only 2 things I need off of the block and I can take out the crank.

[ForcedFirebird]

The oil pump nut is reverse thread. Look closely at the nut and you will see and arrow that says "loosen".

The crank hub just pulls off, probably is crudded in there. I use a slide hammer and a bolt on one of the holes, or a 3 jaw puller.

[m3boost]

just unbolt the whole pump..tilt it forward and remove the pump

[TobyB]

Or put the bolt back in a little,
hang a 2 or 3 jaw puller on it, and tug.
Once it breaks loose,
it comes off pretty easily.

+1 for leaving the oil pump sprocket on the pump....

t