[DaveWM]

do you know how much of an adjustment you may have made on T704?

FYI at most the L704 would be 1/2 turn either way, and the effect is instant (as soon as you move any at all the number of rolling bars should go up or down. Down is the way you want until it locks, again for me this has been about 1/4 turn). generally speaking if adjustment of coil does not have an immediate response, its likely you are adj the wrong coil. Coils are resonate devises not like pots that have a more linear response.

the tube you want to swap 1st would be the reactance/osc 6U8 this assumes you really have a color osc problem.

I pic of the color snow from the color killer adj was requested to confirm the color osc is running and working as it should(since I had no pic of the rolling bars).