crank and pump defo match, I was quite aware of that before purchacing

Still not sure where I stand as far as shells are concerned Just to recap:

--- Im pretty sure I have a late block.

--- The shells I have fitted my old block perfectly. This block was chucked due to cracked oil pressure switch hole.

---The same shells now sit wanky in the good (late?) block.

I think I will invest in the later shells (only one groved) and see if they sit better.

Thanks for your help gents, more gems of wisdom are welcom if anyone has any