Well I never put a tiger rack in an alpine.I have put the mustang rack in.I have added Mustang spindles with a Mustang rack.I have redesigned the front end using Mustang shock towers,Mustang A arms and spindles and the Mustang rack.
In each case the crossmember must be modified.Tie rods will need to be bent as ala Tiger depending on what route you may decice upon.Steering arms need to be reversed and modified.Mustang spindles eliminate steering arm problems.You will need to add Ujoints and a shaft plus a bushing as well as maybe a stand off to do this safely if you are not using a tiger rack and steering shafts.You also need to change the column.
This is just a slight look at what may be involved.Of course I have done the V8 conversions which led to some of what I have done.
If you are running a stock Alpine or a V6 conversion why would you want to change the steering.The Alpine steering and front end is VERY GOOD.