I would have the rod in front of you, measure the I.D. of the guides before and after, note if it has an insert or not, the finish color and single or double feet. Then log on to http://www.jannsnetcraft.com/Content...ildingTips.htm. This page has some basic info including some standard guides charts that should give you an idea what you're looking for.

Then goto this page from Jann's http://www.jannsnetcraft.com/Content/techService.htm and choose your method for a experts advice. They have a live on-line chat, but calling and asking to talk to a rod building expert will get you quicker results. They should be able to quickly help you find the right guide.