The word sparkling is unusual in that you can form a chain of nine words by taking just one letter from each preceding word in the chain. If you then assign each letter a value equal to the number of letters in the word you removed it from - such that if you took R from GIRL, R would equal 4 - then you would have completed the first part of this puzzle.
To complete the puzzle, find a way to use your values to turn these words into numbers. Assuming 51N & 00W
ILK x KIP x RIG + GRIPS + RASP
GNARL + PLANK + RIG + SKIP
You can check your answers for this puzzle on Geochecker.com.