I have a 2001 with the 3.0 OHV engine and it has the small spring set heads that I am replacing. I screwed up and ordered a set with the bigger spring set and valve stems, will they work also or do I need to ship them back? Please help. Thanks

 

You should be fine.

Read here on the changes to 3.0l over the years: Ford Ranger II 3.0 liter Engines

In '99 the heads were changed to smaller valves, 8mm('98 and earlier) to 7mm

But I don't think rockers or cams were changed

 

looking for help with 3.0 v6 cylinder head gaskets issue can any one help.. its pretty serious Thanks