When I use reproduction parts I have to research each first on the sites and find out who makes an acceptable part. From there I base may choice on who I buy if from on how quick I need the part, if I can lump together multiple parts that the same seller carries (to reduce shipping costs) and how easy the seller has been on handling problems or issues that might arise. One bad experience will quickly wipe away any benefit of a slightly cheaper price.
These three things (everything else being exactly the same) help me make the choice.
NOS parts if used (have to be REAL careful since NOS can many many things and allot of NOS parts are not the best choice always for a restoration) are sourced from any of the trustworthy vendors and individuals that has the specific parts. You don't always have allot of choices on selection when it comes to hard to get parts. More often its making the decision related to if you want to spend the $$$$'s it might take to purchase the part. A very personal choice
NOS Parts - Seems to be that ads placed on multiple sites in the wanted section will bring sellers with that hard to find parts, to you then after pictures, prices and discussions you get to choose between the offerings or choose to wait for something better/less expensive. Always keeping in mind that you may never get that opportunity again. I've got items I've been looking for for 25 plus years
Restoring Parts- If you choose not to restore the parts yourself I would suggest that the forums are the best location to research, ask and read about other peoples experiences. There is nothing IMHO better than independent testimonials on forums from multiple members that you have seen over and over again. Or a vendor that participates in the sharing of information and knowledge on the sites. With that said its not easy for most of them to spend too much time on forums since they have families to feed and bills to pay
Remember that when using these services you are going to pay for their special knowledge, skills and making you task easier
There is a fairly large cottage industry that has sprung up over the years that support the restoration world. Most of these are small shops that provide a well focused set of products and or services to us. They provide a great service to us and almost all realize how important word of mouth is to them and their future. There are at least a dozen or two of these places/people most have been mentioned on our sites pages.
Parts Cars - Depending on what shape the car your going to restore is should help you decide if you need a parts car. If you go that route make sure its from the same assembly plant and the same time period. IMHO a fairly complete rust free parts cars can be the BEST investment you can make but its a path not often chosen by your regular Mustang or Shelby restorer for some reason when its been a common practice for most of the classic and older collector car restorations. Maybe its the false idea that everything is available in reproduction form for the pony cars and that allot of builders and owners now a days don't want to get their hands dirty or just want a "Easy" button.
Just my observations - trying to keep the response somewhat short
