GM-GMC: Ignition, gmc 1500, salvage yard

Question
I own a '88 GMC 1500 Sierra 5.7L 350 2 wheel drive. I recently tried to start my truck and the key truned past the lock and run positions but did not catch in the start position. I tried moving the Gear shifter to see if that would help but it did not. The steering wheel lcoks when I remove the key.
I also tried to rocking the truck to see if the transmission was causing it to be stuck.

Any help is welcomed.

Lee

Answer
My 84 GMC K2500 recently had the same problem.  A piece broke off in the upper steering column and the lock cylinder could not force the rod down into the ignition switch to make the starter work.

I do not know if your 88 GMC is set up the same way, but I found it quicker and easier to buy a used steering column from a salvage yard and I installed it to cure the problem.

It could also be an ignition switch that has gone bad.  You have to lower, but not remove the steering column to gain access to the switch, which is on top of the column near to where the column passes through the firewall.