Yes, my non-OEM receiver had spacers between the receiver and the frame. For some reason, EACH BOLT has it's own spacer on mine. My spacers were 3/8", whereas the GGM spindle attachment is 1/4". So I had to make up an extra 1/8". I used washers.
In your case, since you have no spacers at all, unfortunately it seems you'll need to drop the hitch and provide spacers at the other three corners with a 1/4" spacer. In my pic below you can also see my broken bolt head where it was welded to the frame. The ugly shear on the shaft is where I cut it off with a hacksaw, I didn't have an angle grinder available that day. I really wish I had used PB blaster and heat, in hindsight.
I have some pics of my replacement hitch bolts here:
I wanted to post some pictures and observations of my GGM tire carrier install I completed this weekend. Original thread below in the Vendors' section if you haven't seen this new product yet. This is the first step to someday installing a sub-tank...
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