fuel line diagram or help???

[titan]

well my self and pinny have sort of located the area of the blockage in the fuel line it between the sediment trap and the tank it could be to do with sender unit (going to replace ) or in the fuel line its self im currently running the disco on the return pipe line from the lift pump.

now the problems i have are

1) how far does the return pipe go into the tank i cant remove the sender unit as the connections ar corroded and if i remove them ill be with out it untill i can get a replacment this is just so i have an idea when i need to refuel dont wont to run out

2) is there anything in the sender unit that could be harbouring a blockage like a mesh on the feeding line or could the pipe work in side the unit be corrorided and that coursing the blockage

3) dose anyone no where i can get new fuel line conections from and /or what size they are and wat thread they are also is there an inline connection i can use so i can cut the pipe already on and just fix a new bit in ??

4) last one is there a diagram of the fuel system any where and /or a side diagram of a sender unit i need this as i may replace the hole line i can trace it but as a temp measure i wont to put a stright through pipe from tank to the lift pump and need to work out where it has to go

when pinny ran some test on the fuel line one of the thing he did was syphone the fuel from the tank through the feed line this was a task in it self which is wat we belvie to be a blockage but on the flip side to blow bubbles into the tank was easy could this be a valve gone or a none return valve be replaced the wrong way????

any help much needed

ops one more i was told it was 8mm pipe is this correct ????