1995 Toyota Pickup spark plugs

I am changing the spark plugs on my 1995 toyota t-100 pickup. I ended up with single electrode ngk's (this was the parts store recomended plug), however, when I pulled out the old plugs they turned out to be dou-electrode plugs. I checked the manual and it says use only duo-electrode plugs. The parts store is still saying I have the right plugs. Can I use single electode plugs or not?