sounds like the horizontal adjustment to me...adjust it a little and see if it changes..
I think you mean the vertical adjustment.
it's not uncommon for you to have to redo all the color bias settings on these after recapping them. in fact, you have to do a LOT of adjusting on them, particularly as Dokert mentioned with the B+ adjustment.
to test the B+, I personally use alligator clips, if you look to the center of the chassis, you will find a pin labeled BJ, that's the test point for B+. hook your red wire on your meter to that, and the black wire to the metal monitor frame.
for color bias, I turn them all to the halfway point, and then if you need to add a color to fix the white balance, you do so accordingly. it should be worth noting that the last couple monitors I did in my PC-10, I had to reflow the neckboards and the color inverter boards.
your icicle syndrome though sounds like the red is up too high and smearing. there's 3 brightness adjustments, I have ignored the middle one (a funky horizontally mounted pot north of the flyback) and knocked the flyback (the main aka coarse) brightness down, and then the Brightness pot to where your black background is black -- turn it up to where it's grey/brown, then step it back until the pixels disappear.