Chrysler electronic Odometer

Hi, I have a 1993 Chrysler Town and Country mini-van 75k miles no major
repair work performed on the van. Recently the electronic instrument
cluster started cutting out every so often.

The dealer’s best efforts failed to find anything wrong and the
intermittent cutout is to fast to trace. I can’t afford to put any more
money into tracing. I asked the dealer if I could get another electronic
instrument cluster to insert and see if it was in the cluster circuit, ECM
or else ware.

I found an identical one with 160k miles but the dealer said I would need
to switch a matched set of ECM and electronic instrument cluster or the
higher miles will overwrite the original miles on my ECM. They want $325
to rewrite my miles to the replacement ECM.

Does anyone know if I can switch out the original computer and ECM, run a
test and replace the original ECM and electronic instrument cluster
without loosing my mileage or paying to have the dealer transfer settings?
Thanks for any suggestions