Another keyless entry problem. HELP!!!!!

Ok, here we go, i own a 98 blazer ls that didn't not come factory with a keyless entry system. So recently i got a remote and receiver out of a 2000 blazer and tried to get them to work in my 98. I plugged the module in the correct spot under the driver side panel near the parking break.

So i tried to program the remote and i could not get my blazer to go into the programming mode. (I did the hold unlock while turning ignition key on, off, on, off.)

So then i went to the chevrolet dealer in town and they got my vin # and the number's off of my receiver module and remote and they said it would all work. But they also said the they would have to program the module to the truck's computer cause the computer is not picking the receiver module up.

My question is this. Do i really need for them to do this or are they just trying to get my money. Could i just disconnect the positive on the battery to reset the computer and maybe it would pick it up or is there another way to do this?

Oh, and by the way i know that the remote works.

Any help would be greatly appreciated, thanx!!!

I did the same thing, also - had to replace my battery today and that didn't fix the problem.....

Still searching for the answer to get the keyless entry to start working on mine.... I have a 2002 blazer.