Why did george grenville attempt to reform the colonial customs system after 1763?
he wanted to promote better relations between the colonies and britain.
he discovered that the colonial customs service paid out four times more in salaries than they collected.
he believed that the colonists paid too much in taxes.
he knew that london was too corrupt to handle the job.

He attempted to reform because he discovered that the colonial customs service paid out four times more in salaries than they collected.

Explanation:

As Britain was trying to recover from the costs of the Seven Years War, George immediate task was to restore the nation's finances. He also had to deal with the fall- out  from  Pontiac's Rebellion, which erupted in North America in 1763.  One of the most proeminent measure of his administration was the Stamp act, which was an exclusive tax placed on the colonies in America requiring that documents and newspapers were printed on stamped paper from London bearing an embossed revenue stamp that had to be paid for in British currency.

"the royal proclamation of 1763"

b

being given a fair trial before a jury