Toxteth Customs Offices

Hi I am new to this forum so please be patient
I have two Customs Officers on our family tree who worked at Toxteth at different times
One James FOLLAND seems to have been there from 1830 The other William Henry Kelly died aged 33 in Toxteth having served in Appledore in 1881 he had a child born in Bow in 1883 so must have arrived in liverpool after that date but died in 1890
I would like to know if there is any way of following either man in the customs service Liverpool and particularly if William kelly's death was related to his work as a customs boatman
Many thanks in advance
Trees