Tach... MK2 Motometer on a MK4 TDI alternator

[X@V]

Hi,

I have a '03 ALH TDI into a '92 Jetta (it was a 1.6TD)

I want to use the stock MK2 cluster, but it indicates ~1100 instead of 900rpm at idle.

As I know, the input is a 0-12v signal. The frequency is wrong for my cluster (reading 903rpm on the vag-com, it's electronic TDI, not a M-TDI)

Is there any solution?

Thanks

[X@V]

I found a 22k pot on the board... is it this one? (R3)