Hay Dude! Happy Monday.
The factory design used bolts that held the spring plate inplace. converting to a stud is considered stronger. I haven't done this my self as my 60 came with the studs you see in my pic. I have a much thicker plate than you too. The gap under the plate is needed to keep the down pressure even with the U bolt side so don't put anything under the plate
I would get something different in there..the stack of washers doesn't look right, I would be a bit nervous running it like that, probly fine for around town drving but nothing more.
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02c
Burt