@chakster , Your Lustre 801 has only the (thin) armwand
made from steel. The same apply for the SME ''R'' kinds.
The effective mass by FR-66/64 S depends from the used
headshell and counterweight. I never used any of the FR
headshells because I consider them all as worthless.
For the FR 66/64 series 3 different counterweights are made:
standard, 170 g and 250 g. One should use the weight which
can be moved nearest to the pivot. The least inertia is the
result. The worst headshell is S3 ( 19,5 g). The other are to
short for the usual headshell wire length. So the effective length
is not easy to adjust (stylus ''distance'' to the pivot). I prefer
headshells made from magnesium with ''movable 4 pin connector''.
This kind make azimuth adjustment possible as well the added
space for the stylus adjustment.