RCA CTC-? What to do with?

[zenith porthole]

I picked up this set a couple of weeks ago and was quite disappointed when I tried it out. The picture was completely green, with only a hint of blue at the bottom left side. My initial thought was that the red and blue guns were dead, and that I had just purchased another set in need of a new CRT.
I swapped the chassis this evening with a spare from Captain Moody (a million thank you's!) and was quite surprised and pleased with the result. The colours are quite briliant and vivid, but the picture appears a bit out of focus, as if the colors are shadowing one another. Color tv is a whole new ball game for me. Any advice on fine tuning the picture?