What a fun kit that is! Good find!
I built (and still have) the original 1975 issue, bought at a Goodyear tire shop no less.
I also picked up an unbuilt and complete kit in like-new shape recently at a modeller's flea market for ¥2,500 (about 25 bucks USD). I'm looking forward to reliving the magic!
Be sure to post yours up when you get 'er done!