How do you separate 1981 Kelloggs cards and still get submittable cards?

I bought 6 complete unopened sets partially becaue of the low price, but mainly for the lack of or low pop PSA 10's of many HOF'ers. I think my lack of experience separating them caused me to ruin the one that I did open. How the heck do you separate them without damaging the corners? Does it even matter to PSA if the corner is missing?
Here's a 10 on eBay. Notice the corners.
PSA 10
Here's a 10 on eBay. Notice the corners.
PSA 10
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Comments
Im glad you can fulfill some peoples needs for serious hobby talk.
edit: I said score uhuhuhuh
1994 Pro Line Live
TheDallasCowboyBackfieldProject
1994 Pro Line Live
TheDallasCowboyBackfieldProject
<< <i>This thread is a disgrace to the forum. >>
Lol
1994 Pro Line Live
TheDallasCowboyBackfieldProject
1994 Pro Line Live
TheDallasCowboyBackfieldProject
<< <i>I scored with quite a few 8's but married a 9.5 (She was a little OC when we married so couldn't get a 10). >>
If she's a 9.5 you better cross her over cause she sure aint in a PSA holder.
GOSH!!