As some of you know I put some after market gauges on my 89 RS. I put a "T" on the manifold in order to try & keep the stock gauge hooked up also. The "T" is to far up for both gauges to work at all. I took the "T" off, and hooked up just one gauge. It works now. Question is. Will it cause any problems not having the stocker, wired & working properly? Is their another spot on the manifold that I can hook the new gauge too? It's the 305 TBI.

I take it you're asking about the temp gauge. Yes, stock sender back to its OE place.
Aftermarket sender can go on the pass cylinder head between cyl #6 & #8. There should be a plug there to remove and install the sending unit, just the opposite of the driver cyl head.