So after you buy the a arms you need to do this extra fabrication?

I am aware of the difference just surprised you need to mod after spending the cash.
I will be going Fireball in the future

Let me clear this up, I ordered A arms for a 87, the arms I received were for an 87, the issue I had was from ordering an 87 A arm rebuild kit, upper and lower stock, the difference was the upper A arms had the 1 piece tube but was a smaller diameter and used the same bearings as the lower A arms instead of larger bearings that the OEM uses so the only parts usable out of the stock upper rebuild kit was the long inner race tubes, bearings and seals were too large O.D. If your inner race tube is good buy a 88 kit for upper and lower A arms. If inner race tube is rusted/pitted you may have to buy the 87 upper kit for just those, unless you find a source for just the inner race tubes, the upper kit was $87. Lee