Personally, I have the best luck when I set the angle between the steering link and my servo saver at 90 degrees. In this way, the servo saver will actually lean in towards the top deck a bit when centered.
On both of my cars my endpoints are within 1 point. I have a formula that I follow when setting my endpoints but it escapes me right now.
Here is a quote I got from Xpress and I find it invaluable. I use this method on every car and my steering feels much more consistent.
"You just need to adjust the sub-trim and link length to make the end point values equal. If you have a higher endpoint value turning right shorten the link and adjust the sub-trim so the vehicle tracks straight. If you have a higher endpoint value turning left lengthen the link and re adjust subtrim so the vehicle tracks straight. It takes a little time to get right, but it all centers around having the proper angle between the servo saver arm and angle and length of the link connecting to the bellcrank."
You don't want the ball stud on the servo saver directly above the servo output. You need a 90 degree angle between the link and the servo output shaft/ballstud line.
Now, this was advice for my t3-11/12 and I find the T4 is much more close to staight up and down than m,y T3 was. My endpoints are exactly the same however.
Basically it comes down to this...
higher endpoint right = shorten link, recenter using subtrim
Higher endpoint left = lengthen link, recenter using subtrim
Before starting make sure your steering links are the same length.