Can someone provide some guidance on the repair process for this keel? I will check & repair the keep ground strap in the sump to eliminate the likely source of the trouble. I need guidance on the keel rust repairs.

The vessel is the 1982 Mango Hull Number 29, formerly Windrush currently named Jupiter, on the hard for a refit in Annapolis.

There are pinhole rust points on the keel (pictures attached). I have been able to get in and explore with an angle grinder & flap disk. In the pictures, the pinhole rust spots were ground to clean metal and then covered with Acid8 rust converter primer to prevent flash rust. 

Almost all the areas aggressively ground and primed are stable (no change). 

Active problems:
In one area that I did not aggressively grind out, there are some re-emerging small re-emerging pinholes. I will re-grind and reprime.
In two areas, there is still weeping in 2 areas.

Should I fully sandblast this keel? Or is this overkill? Is it wasted effort to strip the entire keel?

The areas I have already stabilized will be treated with acid etch/rust convert primer, epoxy, fail, apply totalprotect, and bottom paint. 

Any guidance or wisdom would be appreciated.

Thank you,

Charles
SV Jupiter