I'm assuming there is an inline fuel filter (not the one at the carb). Where is the one in the fuel line? Thanks

 

What year is your Caprice?

 

1975.

 

Any inline filter for that year would be in the carb. Never have
found an OE filter on a SBC vehicle elsewhere.

That said, I'd put it in the suction line before the fuel pump
(mandatory if you go to electric pump) and go as big as possible
since you may have a lot of fuel tank sediment by now (my
original tank rusted badly inside).