After a long search I found this :
"The early 060 use the mask 1F43G (Rev.1) that can run up to 66 MHz. The last mask is the 1E41J (Rev.6) and allows to be over-clocked up to 100 MHz, but the Rev.6 cannot be found at a decent price (the price is > 400 EUR !)."
There is a turboboard for the Falcon that is based on that latest mask. Here is the link :