Radio Carbon Dating a Halfback 4x12

Hi. First post.

I'm looking at a halfback 4x12 that I found a guy selling and it looks to be mid-eighties, but I'm not sure and was wondering if anyone had any thoughts.

I used to own a halfback 4x12 w/ a .50 Caliber + head that I bought in 1990, but sold.

This one appears to be older because the handle on the side of the cab just says "Mesa" and I'm pretty sure the one I had said Mesa/Boogie.

Anybody have one similar or know about when this design was in place?

Thanks!

Here's a link to a pic of the handle.

https://drive.google.com/open?id=0B4J-LCncXYhzaGFLRjBEU1VMY2c

My 1986 4x12 with metal grill has no name on handles. I was quite disappointed when it arrived but does it ever still kick major butt!

Yeah the early 4x12's (and 2x12's) had the "knife edge" handles with the earliest models only having "Mesa" on the handle.
On later models (still early 80's) the handles had "Mesa Boogie".
Sometime in the mid 80's they stopped using "knife edge" and went with the round handle (which had no place for a logo).

Also maybe of interest the earliest 4x12's had a "Boogie" logo on the grille. It was similar to the logo used on heads and combos but larger.
Later on for 4x12's and 2x12's they went with the "Mesa/ Boogie" logo plate.