Never seen or heard of a stock Tele with block position markers, either.
The oddest thing about this one may be the 6-28-88 penciled on the butt-end of the neck.
Starting in the mid-70's, USA-made Fenders serial numbers on the face of the headstock started with letter prefixes: 'S' for Seventies, 'E' for Eighties and 'N' for Nineties. with a 6-digit number following. The first digit of those 6 indicated, approximately, the year of manufacture. For example, E1+ 5 digits could be made from '80-82.
Some Fender Japan product used 'E' & 'N' prefixes in the '80's and '90's, and that mucked things up a bit, but still, a Japanese Fender clearly should say Japan on it.
With this odd Tele, the s/n starting with E3 dates it between 82-84, maybe even 85. It would have been made in the Fullerton, CA plant, at leat according to
Guitar Dater Project, that serial number with Made in USA on the headstock returns this info:
Your guitar was made at the
Fullerton Plant (Fender - CBS Era), USA
in the Year(s): 1982 - 1985
However, that same serial number, if Made in Japan, Guitar Date Project returns this tidbit:
Your guitar was made at the
Fuji-gen Plant (for Fender Japan), Japan
in the Year(s): 1984 - 1987
Here's an interesting and comprehensive source on Fender vintage info:
Vintage Guitars Info on Fender