Blue Peter Dinghy - Sanding to a shine

Today I started to sand back to a shine. I started with 180 grit, then 240, 320, 400, 600 , and finally 1200. This has brought the boat back to a very smooth, but matt surface finish. Later on I'll have to use a polishing grit and lambs wool cloth to get it back to a gloss (I hope!!!).

Sadly, With the sanding, some areas have been sanded right through the gelcoat. This tends to be where I've added a fibreglass repair, then given a final coat of resin to seal. It is really really frustrating, but I've had to grind these areas back just a touch. They won't go fully opaque after sanding back again, but they'll certainly look better than at present. Also, I've noticed some tens of pin-hole holes in the both new and old gelcoat. In all instances, I've ground these out, and they're now filled with the last scrapings of gelcoat from the pot (fingers crossed they look okay once sanded!).

I've been pretty luck with the weather on the whole, that is to say, I've managed to dodge showers exceptionally well over the weeks (there've been a lot!). Typically, today, with the final scrapings of gelcoat mixed and half way through application, it started to drizzle. I optimistically hoped it would abate, but it got worse so I ended up having to stop and get some old advertising boards to throw over it before it was drenched. Hopefully I did this soon enough that the new patches aren't ruined, but, as expected the gelcoat in my pot had as good as gone off before I could finish all work satisfactorily. 

Incredulously, I found a 60mm crack I'd missed in my earlier repairs - this has now been ground out ready for filling. Once this is filled, the boat is officially gelcoat crack free!!!!

My plan is to sand these little lumps back to the rest of the hull, sand the areas up to 1200grit to fair them in and then work on the other side again. The top is looking way worse, but, that doesn't impede water flow, so I guess it is important predominately from a vanity perspective only. I'm loathe to buy another 500g+ of gelcoat, at this point I'm looking to get the hull to a point I can leave it - I still need to do something about the badly warped daggerboard and the non-existent transom plate.