ways to join soilds?

[drivefast]

I have a valve cover that has several bolt holes around the flange. Each bolt hole has a rid on one side and a raised and angled, offset threaded bolt on the other. Each bolt hole is identical except for location and angle I know I can join the parts in an assem. and use that to create a new part by joining all the features but then I can no longer easily make changes to the part. If I need to change something on the sketch I have to do it on the pre-asssem. part. Is there an easier way?

 

[CorBlimeyLimey]

Sorry, I'm having trouble deciphering your post and picturing what you describe.

The image I have in my head is of a valve cover with protruding angled studs?
If that is correct why not keep it as an assy and use it as a sub-assy in upper level assys?
Or create it as a multi-body part. The bolts (studs) can be inserted as parts into the cover part.