When solid axle swapping an F-250 with less than 3" of lift the flat pitman arm is useful to get the full steering on the Ford straight axle.
-F-350, factory Dana 60 axle
If you're installing the 3 inch reversal using stock worn out springs, we don't feel its necessary. The reason is, your not gaining 3 inch's of lift over stock, your compensation for old springs, probably only gaining 1.5 -2 inch of lift, some times less.
-F-250 installing a reversal and Dana 60 80-97 axle
The f-250 has a shorter throw than the F-350, so to get full turning radius you need to either swap on the Factory F-350 arm or this drop arm. The determining factor is if you are using new F-350 springs, or refreshed as some springs shops term it, you should use the drop arm, which is only actually 2 inch's of drop over the f-250 arm, but longer to allow full steering. If using worn out springs, then switch to a stock F-350 arm.
-Super duty leaf conversion ( FSRSD ). Yes, its a 4 inch of lift.
-Super duty axle leaf conversion. (FSRSDAL) Yes, its 4 inch's of lift.
-5 inch Shackle reversal under anything
Yes, its a 5 inch lift, and if your adding it to other springs you need either our Ball Joint 60 crossover kit, or a king pin 60 cross over steering kit depending on donor axle, not just a pit man arm.