Twombo,

Fuelpumps on ALL B18 and B20 engines:

'62-'64, AC the one with the glasbowl
'65, AC with metal-bowl
'66-'70, Pierburg

All three types where originaly mounted with the spacer-brick and there where/is no difference in lever.
There would be no adaption needed - the specifications are the same all the way thru the years. -And pumps can be switched over any way.

All this, from an original point of view! Aftermarket fuelpumps - I don't know!

But today Volvo sell a newer design of the Pierburg and I know of one Italien one too..(but anyone who knows Italien autoparts don't really wanna go there..)

Anyway - if what you have is an original pump - the spacer-brick MUST be mounted together with the pump!
(Only the AC pump (looks exactly the same as the one for the B18/B20's) for the B16 engine is different)

If your fuelpump is not working - but you have the original one, it is fairly easy to restore the pump with a "rebuild-set" - and rebuild-set's are available for all 3 original types..

I have noticed that a lot of brickboarders seem to have replaced the original fuelpump with electrical fuelpumps - which I dont really see the point in - other than you might have difficulties in getting the rebuild-set's or original pumps..
Anyway - without even having looked at costs and so - I would still guess that mounting a pump that gives too much fuel and trying too avoid this by inserting extra fuelreturn-lines or whatever - can't really be THAT more cheaper than to go for the original pump and benefitting the original looks..

Sorry if I sound tuff - not intented! :-)
/Soren