Placement of lock-ons

Take a piece of your track and study it carefully, following the circuit made when a connection is made to one of the outside rails, how it is physically connected to the cross ties, and how there is no current conducted(short circuit) to the center rail(due to the insulators). Continue on past the center rail to the other outside rail and observe its physical connection to the ties, and I think you will see the answer.

GG-1 fan,

Your thinking is correct. Go for it!

You ok unless you have an insulated rail section (for triggering accessories).

Just a suggestion.....Lay your track out the way you are talking. Now power up your transformer. Using your handy-dandy test meter check every section of track to verify that all is fine....so far. If you're happy with your findings, power down. Place your engine on the track. Make sure that you DO NOT use one of your favourite pieces. Now power up and run you locomotive through its' paces. If everything proves to be acceptable, transfer your test track to your layout. I hope that you find my suggestion helpful. I'll go back to my senior citizens corner now.

Thank-you for the suggestions.  I do, in fact, have some insulated sections for accessories like a crossing gate.