Here's a way to a 1937 Guide electrical parts catalog with all info on headlights, lenses, reflectors, tail lights, etc, for cars and trucks from the mid 1920's to 1937. Some good info is available from an archived web source. A site called DonsBulbs.com had a huge variety of information on any type of light bulb plus a great reference library. Unfortunately Don retired and that website is closed, but you can still access info from The Wayback Machine. Here's how if you don't know Wayback:
1) Go to the Wayback Machine archive at
https://archive.org/web/2) When that page opens look for a text box next to the large Wayback Machine letters. Type in DonsBulbs.com and click the "Browse History" button.
3) In a few moments a year by year calendar page will open. We'll want to open donsbulbs when he was still active, but still new enough to capture recent updates that may have been made. So just for an example click on the 2013 box, and when the 2013 calendar opens click on April 2 and wait a few moments.
These are example dates, you can try any combo you want.
4) An old web copy of donsbulbs opens. On the left hand side under Reference click on Library. When the Library page opens scroll down and click on the thumbnail of the Guide Universal Catalog #806. When the next page opens with an index scroll down and open pages 67, 68 and 69. These are the IHC pages. There are separate listing for each year of the C-1: 1934, 35 and 36. So interestingly this catalog indicates that C-1 headlights came in different styles - Tiltray or Twilite, in black or chromium, and in 9-1/8 and 9-7/8 inch diameters. Some individual repair part numbers are listed as well. Part illustrations of all kinds are in the catalog. Don't get lost in the library, it's the Holiday Season.
5) I'd recommend downloading and saving anything of interest out of the library section. Who knows how long it will stay archived. Note that the bulb search function does not work on this archived site.
6) So there is your Guide catalog. Or you can buy a staple bound reprint from Amazon for $38.95. Your choice.
/Tom