The most important thing you are missing is conifers grow till they die.

If you plant a dwarf conifer and live long enough it will out grow the limitations you have placed on it.

Most height/width given are for 10 years growth and will vary due to micro-climate.

There are many columnar fastigiate forms of conifers but your height limitations eliminate most forms. The 8 ft. you want it to stop growing at is not doable.

Hopefully others will chime in for further help.

Dave

Dave, thank you for the information. It certainly gives me a new perspective in thinking about this. I may need to consider a different group of evergreens to find a candidate for this particular spot. It sounds like I may want to consider other places in my yard for a conifer, as I do like them very much.