1. Use a hack saw and cut the bezel in two places, 180 degrees apart.
2. Remove the two resulting pieces of the bezel.
3. Throw them away.
4. Fix the screws.
5. Then replace the bezel using 4" heat shrink tubing.
Here's the sequence:
Get a Pimento Jar Lid (upside down):
1. Buy a one foot section of 4" heat shrink tubing.
2. Cut a 15/16 in strip of tubing from the one foot section.
3. Prop the Speedo / Tach face down on a .31 in high round "thing". I used a lid from a small jar of "Dromedary Diced Pimientos" (upside down to accommodate the slight curve in the glass)
4. Place the 15/16 in strip of heat shrink around the bezel.
5. Apply heat from a heat gun evenly all the way around.
Notes: The .31 dimension is from the front edge of the bezel to the work surface, with the tach / speedo face down on a suitable prop. You have to allow for the slight curve of the glass. If done exactly, there is no trimming required. A lid from a small jar of "Dromedary Diced Pimientos" works perfectly because it forms a cup to keep the glass curve from wobbling when you apply the heat.
"Drape" the tubing around the speedo:
Apply heat carefully and evenly around the circumference of the speedo. If you don't have a heat gun, use a hair dryer on high. If you don't have a hair dryer, get a girl friend, she's got one.
The tubing will "curl" around both edges of the bezel.
Ignore that glass of wine in the background... :

..it's not part of the process...neither is the mug with the "Golden" on it...that's just her dog food measuring cup....

..the Tums are there for all the stress that the dog and drinking create.
Here is the final product:
Here is a pic of my '81/H with both the speedo and tach repaired. The speedo had a broken needle, which I repaired with a small piece of heat shrink tubing. The tach had a dirty glass inside.