Paul,
Thank you for responding.
I actually called yesterday and spoke to a very nice representative who looked at the additional pictures I had just sent comparing the size of a nickel to
21-174 roller guide's diameter. For the height I took a nickel and put a penny on top and that was the same height as roller guide
21-174.
I ordered the parts yesterday and receive confirmation a little while ago that they have shipped.
Thank you for your help.