need some help determining the differences between 60-66

[63_chevy]

Ok so I know a guy who is a 60-66 Chevy truck enthusiast like me and he thinks he knows EVERYTHING on 60-66 Chevy trucks. Now I have a 63 c10 and he swears it’s a 61. Reason is he says the double hump dash is 61-62 ONLY! And I cannot change his mind... now like I said I have a 63 c10 but I do have a 61 c10 grille! now correct me if I’m wrong but from my understanding the double hump dash was from 60-63 and the other differences were that 60-62 frame was different and 60-61 hoods, 63-66 frames were the same and of course the changes in the grilles from 60-64 and emblems from every year were different. Is there any way to tell if my cab is a 63 without the VIN his argument was someone could have changed the VIN plate, I can’t go off the frame because it’s a factory 2wd swb on a 75 swb 4x4 frame. I also know the lights are stamped with the year to but I robbed my tail lights off a 60 c10 and the turning signals off a 65. The truck also modern tilt steering colum but I have a colum from a 62 gmc. Can anyone tell me what all the differences between the years and if there is anyway to tell what year my cab is? ill post pics of my truck in the day light i have one but the grille isnt in the truck