[Boatanchors] 388 cabinet?

[Bob Young]

Hi all,

I bought a cabinet that was advertised as a R-388 51J cab, it fits perfectly 
and looks perfect except that the rectangular opening in the back is about 
an inch too low for the SO-239 connectors, there is only about 1/4" 
clearance between the connector and the back of the cab. It also has a 2 
1/2" x 1" oval opening on the back approx. 4" from the bottom and 6" from 
the right side facing the back of the cab with no corresponding connectors. 
Any ideas what this is? Different model 51J perhaps?
I can send pictures of the original auction if anyone is interested to see 
it,

Thanks,

Bob Young
Millbury, Ma
KB1OKL