Lister Domestic pump rebuild

Hi, very new here but owned a D Type for years, but not rallied for ages. Have at last got a water pump which I intend to use for its original purpose shifting water around the garden. I may also rally occasionally. My question is...how do I remove the plunger rod? I've undone the castle nut and removed the old cup washers and could replace without further dismantling, but it seems a shame.

Any suggestions and perhaps a point in the right direction for any running instructions would be good.
Thanks,

Andy

To remove the plunger rod take the back cover off the crankcase, remove the big end cap, take the crank out and pull it out from there, a lot of work, if your bearings are good I'd leave it in.

Thanks for that. I thought that might be the case. It all feels sound at the moment but I will strip it down so I know whats going on in there.
Thanks again.
Andy