Horizontal lines on picture

Question

Recently repaired field / frame vertical stage replace vert amp IC301, C432 ,( D431 & R431 blown) set is now working,however the picture has a few horizontal lines in the centre and bottom of screen i presume i need to know how to access the service mode to do vertical alignment as the Vheight is a little out.
Does anybody know how to access the service mode on this set please help.
Thanks in advance.