eberspacher D5LC ECU interchange

[Pinzgauer Pete]

was wondering if any of our members has ever tried to use another ECU on their heaters?. I just purchased a D5LC heater but do not have a ECU for it but have a ECU from a D8LC which has the same pin configuration, size and housing. I will purchase the correct ECU but wanted to fire the heater up and wanted to know if anyone has ever attempted such a move or if it would cause damage to my heater? I have been unsuccessful in finding any info on the net, but I am sure I am not the only one who has ever contemplated such a move!