warn 25855 front receiver on 1973, anyone

[swissarmychainsaw]

I want to put a front receiver on my 1973 Suburban, so I purchased what I think it the only option available:
Warn 25855 front receiver
1981-1987 PICKUP 1/2, 3/4, 1 TON; 1981-1988 PICKUP 1 TON; 1981-1991 BLAZER, JIMMY, SUBURBAN, 1 TON R/V PICKUP

Has anyone mounted on of these on an older Square?

The issue is that the front of the frame cups around, which prevents the hitch from slipping in from the front.

Here is the Ideal installation, Note how the front of the frame rails are "open" and you can just slide the receiver between the rails from the front:



Here is what the front of my frame looks like (this is not my truck!), see how the end of the frame rails are cupped:



Is it stupid to "trim" the front of the frame to get this to fit?

thanks
Nick