This engine has 16 spark plugs. Would it be OK to drive after only replacing the top 8? I don’t have time until next week to do the other 8 which are a little harder to get to.

Will this harm the engine at all?

 

I replaced the front 3 plugs in my old V6 sedan, but not the rear 3, and drove for 40k miles until disaster struck.

The disaster was the trans failing, no relation to the plugs.