Hi,
I almost forgot to thank you for your kindness. In fact, I was afraid about the solution chosen by my new colleagues (which are not engine aircraft engineers).
Meantime, I realised that their solution is good enough. I also receive a confirmation from P&WC that the dilatation is small and we will not have any problems with the engine installation (but they don't said nothing about the values). Anyway, this can be measured when we will do some tests.
Once again, thank you. Regards
Fernando