I used to use a very long drillbit for an electric drill, where the tip was the same size as the shaft of the bit, with a small hole thru one end of the bit. 
You drill thru the floor and then thru the insulation below trailer which is about 8-10 inches, and then strip back and run the center conuctor of the drop thru the hole in the bit. 
Push the bit thru floor and insulation onto the ground below and push a decent amount of coax thru, and then grab it from the outside with a layup stick of sorts.  Now that being said, Jones Intercable use to supply us with anything we needed for installs, and $ 1500 Christmas bonuses in 1978-80 era, and I might assume those days are past.
    
    Re: My latest experience
                Member #: 199
            
            
                Registered: 1996-2001
            
            
                Posted:
                
                    356 
                
            
                
                    Name:
                    Chris Kramer
                
                            
                    Name:
                    Chris Kramer
                
                
                    Company:
                    Spectrum Planning, Inc.
                
                            
                    Occupation:
                    VP of Operations
                
                            
                    Location:
                    St. Charles MO.
                
                            
                    Personal:
                        
                    
                
                            
                    Experience:
                    ~40 years
                
        
        Spectrum Planning - The Mapping Innovators
    
    
        This is CABL.com posting #368747. Tiny Link: cabl.co/mbH5H
    
        
            Posted in reply to: Re: My latest experience by webber560
        
    
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