until you get forward of the firewall the lines are 3/8 aluminum tube. once past the firewall your specific engine, mount, injection, along with how you pick up pressure and flow will pretty much drive your routing and specific lengths for flexible hoses. fittings are all standard an with the exception of the special lycoming fittings at the mechanical fuel pump.
my engine from lycoming came with firesleeved hoses from the fuel pump to the fm200 and from the meter up to the diverter. i used a standard vans 3/8 hose from the firewall to the fuel pump and standard length 1/4 hoses for the pressure and for the purge return.
to accomodate the fuel transducer bonaco is making me a couple of short hoses to replace the single 1/4 line.
the typical location to tap fuel pressure is from a tee fitting at the fuel pump... for my routing and mount this positions the supply from the pump poorly and would require a different hose... bonaco is providing a male to female 90 fitting that i had not seen anywhere, a 6500-6-6d that will solve my routing perfectly without other hose modification.