Great decision to get the .35 Whelen. Makes no difference whether it was 1983 or 1988 or 1656, it's one of the greatest calibers ever devised.
I took my Remington 700 Classic .35 Whelen to Zimbabwe in 2001. It slew everything like lightning. My PH was so impressed, he would grab it and leave me with his pre-64 Model 70 .375! He also said if I wanted to return and hunt Cape buffalo, he would sign the waiver to allow me to use the Whelen.
My load was the original top charge of RL15 from the Accurate Manual behind a 250 grain Nosler Partition and that load reduced 2 grains behind a 250 grain Swift A-Frame. The Nosler Partition clocked 2586 fps and the Swift clocked 2536 fps. Both loads shot to the same point at 100 yards and shot at 1", + or -.
I hope you enjoy and appreciate your .35 Whelen as well as I have enjoyed mine. You have the power of a .338 Win Mag with the recoil of a stoutly loaded 30-06.