That's either a back-halfed frame, (No rigid sporties were ever made) or someone ground it or modded the neck. VIN should be on the right side of the neck.
1970 and newer, bikes have the VIN on the engine and frame.
1969 and older, on the engine only,
Your engine says:
3A = XL1000 cc,
H6 = 1976 engine year.
The numbers on the cyinder are casting numbers, as the cylinders were 1000cc jugs, fist offered in 1972.
The rocker casting numbers are the same, only a 1971 part number.
“When the going gets weird, the weird turn professional....” ~ Hunter S. Thompson~
R.I.P. Rubberdown. 1971-2012
2005 E.G. Classic
Baisley Oil spring
Rinehart 3.5" pipes
S&S adj pushrods
3 stickers, adding 5 hp each. I swear......