I've wrestled with these a few times...
My best advice is to find the Koul Tools AN Hose assembly tools. These are available from Summit, Jegs, etc. They make assembling AN hose a far less "prickly" affair.
You should also borrow or buy a Dremel with reinforced cut wheel attachment. Wrap the area to cut with two wraps of masking tape or strapping tape. Carefully and slowly cut thru the hose so you make as few fish hooks as possible. Gently unwrap the tape...dip the end in oil...shove mightily into Koul Tools assembly tool, twisting the hose as you go.
The smaller you go the more difficult it is to assemble. 4AN is a real pain and 3AN brake hose assembly...well, it is nearly impossible.
I could loan you my set of Koul Tools, but you'll have to wait until the weekend after next.
1966 109 5 door wagon 300Tdi "spermaceti fueled"
1994 RRC LeWiB "ruining the air behind me"
1968 2A 88
All my troubles are Rover