I bought a S&W 1026/10MM today. It does not appear to have been fired. I like the controls and the trigger guard checkering. My S&W 1006 is a nice handgun. But the 1026 has some  different features. This is a police model and on the slide "Caution this pistol fires without a magazine".
If the high winds and rain stops I will be out shouting this new addition in the AM.

I was instructor trained on the 1026 almost 30 years ago and was issued one for three years.  I believe the 3rd gen Smith's are among the finest 10mm's ever made.  I also put the P220 near the top of the list.  Two dimples under the decock lever will confirm the factory upgrade was performed. Your pistol was likely a law enforcement model, due to the lack of a magazine disconnect.

dang Terry, how do you find all those old S&W 10mm s??

Yep the 1026 is the 5.00" barrel and is just like the 1076 4.25" with the frame decocker.  Be very careful with the grip removal/reinstall process as if done incorrectly it can damage the decocker.

S&W 1026- 5.00" barrel, frame mounted decocker traditional double action
S&W 1076- 4.25" barrel, frame mounted decocker traditional double action
These can be decocked by pushing down on the frame mounted decocking lever, the hammer is dropped to a half or partially cocked position and pulling the trigger will cock and fire the pistol.  After the gun is fired it is fully recocked and the gun is fired single action till empty or decocked.  The hammer when dry fired will be all the way down but pulling the trigger will cock and fire the gun.  Some models can be fired without the magazine present if the magazine disconnect is removed.  FBI models worked this way...

If you are wanting your gun to shoot with out a mag in place, it's an easy fix.
Remove the rear site from right to left, take the plunger and spring out of the left side, reinstall the rear sight and you are done.
Be sure that you remove the parts from the left side, the similar parts on the right side are part of the firing pin safety system and you want to leave them in place. Be warned that the rear sight is going to be in there fairly tight, so use a sight pusher if you can.
Do not remove anything from the frame itself, ie: disconnector!
If you have access to a parts diagram familiarize yourself with the parts mentioned before you begin, simple job.

I bought my 1026 in December of 93 and added a 1006 two years ago. Last year I found a KCPD 4026 and a few months later a 1076. Obviously I like those models. All are greatly shooters.