Hmm, my 4runner idles right at 750 (adjusted timing and idle screw today in fact, then drove about 80 miles) with the screw about flush with the top. i can't remember what my truck was set at (same year, 86) but i seem to remember the same scenario for screw position roughly. I'll look at it tomorrow to verify.

86 4runner, pro comp AAL, Kayline Soft top, 31's but all stock