I had the R7 vertical at the time on a 3 foot tripod and a 5 foot pole.  So 
the base of the vertical was about 23 feet above ground and the top of the 
vertical would have been about 48 or 49 feet; maybe 50.  Keep in mind, the 
R7 did not have a 6 meter element at the top like the R8 did when it came 
out.  I was tuning the band about this time of the year and heard a Mexican 
station calling CQ on CW about 40 over S9.  I punch the Icom 7000 to 
transmit and checked the SWR, which was 1.4, and the output was 40 watts. 
The X E answered me on the first call.  That summer, I worked 36 states 
using an antennas that didn't have 6 meters on it.
Phil.
K0NX