4x4 not engaging from the 88-98 forum

[Jboston701]

So I got my 88 3/4 ton 350 4x4 up and running thanks to all of you on this forum.
Winter is knocking on the door, so today I tried to engage the 4 wheel drive to make sure it works (I have not needed or tried to put it in 4 wheel drive for several years). The light did not come on, and I could just tell it wasnt engaging. It has always taken its time getting into 4 wheel drive, and Ive heard some years after '88 they changed the actuator to a better one.
I recently had the axle seals replaced by a shop, could that have anything to do with it? Maybe something got broke on accident? Should I start with the actuator? The switch on the t case?
So far all Ive done is ruled out a bad 4x4 light bulb Any suggustions on where I should start? Thanks