Trevor, the secret to the Sals conversion is getting the proper stubs and hubs. Unfortunately there is an equal amount of bad info to all the good regarding part numbers and all that. Be wary of blanket statements like "you can use any non ABS RRC or D1 stub axle and hub". Good luck.
No experience with the Forbyn stuff but those who have installed the converssion seem very happy.
1966 109 5 door wagon 300Tdi "spermaceti fueled"
1994 RRC LeWiB "ruining the air behind me"
All my troubles are Rover