Will this hold my 63 pound black beauty??!!

64 pounds is nothing. If the amp has 4 feet, that’s only 16 pounds on each foot. You’ll be fine. And before someone jumps on me and says that the feet under the transformers will have more weight on them, it will still be fine. It will not be enough to cause any problems.

Uh, you forgot to add the weight of the stand itself. Nice try, though.

My 130 pound amp is on the floor between my 2 speakers...no better place

Wouldn't the glass shelves ring?  That is what I was told when looking for an audio rack.

Have my sunfire 600 (not near 60#) on a bottom glass shelf, bottom shelves as mentioned are not hollow under, they have the steel bracing rungs under the glass, whee the top 2 shelves are pretty much tempered glass with no bracing under.

I use two cutting boards as stands, for my mono blocks.  i garaged them, and cherry stained them, they look great under my amps.

bed bath n beyond, has some nice cutting boards, as u only need one, it will look great on a solid wood cutting board to either side of the rack, or behind, in front....
??

enjoy the ride.