I seem to think that 8 speed freewheels are 5mm spacing which is the same as 8 speed Ergos so there you go.
Might be easier if you have a 8 speed mech but I used an old Record one, pre any indexing, .
Sach freewheel I am sure.
Sachs-Maillard 8sp freewheels came in 4.8mm (Shimano pattern) and 5mm (Campag pattern) spacing - it's all down to the plastic spacers used. Black for Campag, brown for Shimano*.
*That's how I remember it; you've got to have a system, haven't you? </Harry Hill>
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