Here is Cranes XR Series "Trouble Diagnostic"
page:
http://members.aol.com/ajdalton7/xr700.jpg

Also,As the car sat in pieces for years, you may also want
to clean the LED's lens with a que-tip and some alcohol.
If the dist. sat around with the cap off, it may be simply dirt/oil on the optics.
Any other XR-700 users out there, feel free to make a
print. I will leave it for a week.
Arthur