Running Lean

88 4.0 55K miles. After a few months of running like complete junk, I got her going good again! I had to mess with the distributor and TPS a lot, but it runs amazing right now. But when I checked my plugs today, and they were slightly white, just a little bit. Not like white rice, but more like a tiny bit of white mixed in with some redish/brown. Is this OK? or is it a little to lean? is the Spark plug too hot? Should I gap my plugs? I just replaced them with some bosch plugs from NAPA not too long ago.

Thanks!

.035" is the gap and it needs to be set properly. The color you describe is normal. I am not a Bosch fan and prefer NGK myself.