I tried the pin method and gave up on it (too much work). I just let the capillary action handle the work. If looks aren't soooo important, you can follow up with #16 (I think that is the one - the gel) and then even a coat of silicon.
If looks are more the thing, test the job with water and mark any leaks - then just capillary some more intothe problem areas.
I have made 2 - 70g cubes - 2 - 50g cubes and about 3 sumps this way....
Shawn