'70 MGB GT - Front Dampers

[Gary Davis <GDAVIS@ibr6gw80.gp.usbr.gov>]

I looked at my front dampers for the first time last night and discovered
that one was leaking pretty bad.  Can it be repaired or should I replace it?
 Also, the manuals show the damper fluid filler screw on the top of the
damper.  Mine is on the side facing the wheel and it is an Armstrong unit. 
There is no screw on top.  Anyone have an explanation for this?

When using motorcycle fork oil, do you use a heavy oil or a light oil?

Thanks as always - Gary Davis