In looking at my 351 and 302 engine I find that the rocker arms are lower on the push rod side by a quarter inch. On this 289 due to the limited space between valve and rocker arm, I used pushrods that make the rocker arm almost straight (see enclosed picture). Is this going to create any problems for me.

could. See article below:

http://www.circletrack.com/techarticles/ctrp_0609_pushrod_length/index.html

Use the felt tip marker trick or even a dap of white paint to check that the rockers 'sweep' is centered on the valve's tip.

Too long or short a p-rod will wear out the valve guides in a hurry. Ignore too the factory standard length p-rod dimensions since head/block decking, too many valve jobs, head gasket thickness and a few other variables can dramatically affect where the rocker actually hits the valve tip. A Moroso or Comp adjustable p-rod comes in handy here too.

Bob, I don't know where you find all this information, but I do appreciate your knowledge in this area. I have been studying these heads and have arrived at the following conclusions:

1. By not having more of an angle on the rocker arm (shorter on the pushrod side), you risk having the edge of the slot on the bottom of the rocker arm hitting the rocker stud. I found that even under static conditions mine are very close to doing this.

2.However, when using a shorter pushrod, due to the short valve stems, I bottom out on the stud when trying to adjust the valve lash. Since I need the rocker rails, I can not use any valve lash caps to extend the valve length.

3. The roller rocker arms have more clearance both on the rails and the size of the slot. But now from the info you supplied, I find that it is more critical on the centering of the roller.

I will follow your suggested procedure tomorrow and see where I stand with some roller rockers.

i will say this don't try to make a true roller tip pattern. remember there is a closed and open clearence on rocker slot to stud

As probably evident. I'm a Engineer, not a mechanic.
Dan, I'm not sure I understand what you are telling me.
Could you elaborate on this.

i hate typing just to let it be known. did you look at the rocker wear pattern from valve stem contact ? its not a narrow patten in stock form. why waste time trying to get one. the slot in the rocker has a limit of travel, so when valve is closed there should be clearence-- stud to rocker slot same goes when the valve if at full open. this says what the push rod lenght is. can break studs if the meet each other

If you look at the picture ,you can see the spacing is very close. I decided to go to a roller rocker. With the stock Ford pushrod, they were pushing on the outside of the valve stem. By using an adjustable pushrod, I was able to determine the length of what I needed by using the method on the site that Bob directed me to. It turns out, I had to go to a 6.5 length pushrod. I suspect that when the heads were done, they cut the valve stems too short.