You should go through this
http://www.cic.gc.ca/english/information/inadmissibility/arc.asp
Generally it depends upon what grounds he was deported upon, how quickly and in proper manner he complied and how has the situation changed since then. It is written here for instance that if it was illegal work issue, is the applicant in stable work conditions now. If it was a criminal offence, has applicant undergone rehab etc. since then.
At any rate 35 years is a long time. But i believe they are still going to compare the reasons of deportation at that time to current situation at hand.