Hi Rowan,
If you drill out the blanking plugs, or drill and tap a hole in the plugs and use a slide hammer to remove them
Suitably sized plugs can be turned up and pressed back in or tap the holes and fit screw in plugs
I purge out the oilway without removing the plugs, but do not media blast the cases in the first place
Usually the camshaft bushes do not wear badly so if ok leave well alone, make sure to clean out the inner end of the cam bush in the drive side case
Aerosol brake cleaner is good for blasting out nooks and crannies (not crank sludge traps though!!)
As to what to include in the rebuild ? the sky's the limit but you need to make conscious decisions based on future use and maybe financial considerations
I would opt to send the oil pump to SRM or someone else with a test rig for rebuild and performance check
(I now insist on new pumps for customer engines)
Have the conrod big end bores checked for size, if OK polish the rods to a mirror finish, then fit ARP big end bolts
28ft/lbs torque for the 5/16in bolts on original rods
Or fit new rods
I feel its worth modifying the "oil retaining ball and spring" setup to the A65 setup where the ball seats on the back of the oil pump ( that way it can be serviced without an engine strip down)
Make sure the drive side mainshaft is to size for the roller bearing and that the cushdrive splines are in good condition
A lot of crankcases have damaged threads, the 5/16BSW threads that hold the primary cases suffer a lot
"Time Sert" inserts are the best fix
Make sure the oil pump mounting surfaces are absolutely flat,
Remove all the case studs and flatten out any raised areas around the threaded holes
Enough for now
John