maybe a good price for a drop tank, but damn, why not just put a second tank in, like a sedan one between the rear wheel arches, or something like a mk. 1 escort one tucked in the back corner of the boot or something

or...

why do you need it???

if your worried about one trip to datnats take a jerry can

when i did my injection on my coupe i made up a bar across the back for my harness mounts then closed off the boot with aluminium as a firewall. then i had a surge tank and low pressure pump in the boot, but the high pressure pump sat under the car above the tank (betweeen it and the body)

maye a lot of mucking around but it was very cheap (i used what i had)

fuel capacity was never a problem for me either