I would agree that you're ready - more than ready in fact.
I came from Greyskull as well. The GS and 5/3/1 philosophies are very similar - focus on the big four(Squat, Bench, Press and Deads), slow but steady progress and that already mentioned AMRAP sets to name a few.
My only suggestion is this: find a 5/3/1 PROGRAM (developed or suggested by THE Jim Wendler) and stick to it for a several cycles before trying to create your own.
The thing i struggled with, and still do, is trying to do too much with 5/3/1 - this may sound strange, but I would bet many struggle with issue that come from a similar background(coming from a linear progression program).
The Greyskull base is a simplistic design (i ran the base template with just a couple of plug ins); however; 5/3/1 has so many variations and templates(sorry, this seems to be a bad word around here lately) and one may want to add too many options into their programming.
Just my humble opinion
Anyway, good luck and have fun.