M25, running rough, white smoke, low oil pres. Then dying

[Tchiffriller]

So I'm assuming rings and pulling the head now

[KWKloeber]

So I'm assuming rings and pulling the head now

Too late maybe, but first I'd try Ring-Free or Carb-Free to loosen stuck rings before decapitating.  they work really well and sometimes save a ton of unnecessary work.

-ken