I was going to buy a rear view mirror from CCOT - Mirror - Rearview - Head & Arm - 71-09/77 - FJ40/45 - Aft Mrkt - https://www.coolcruisers.com/mirehearm71f.html . They are selling the mirror but do not include any bolts. Any idea what thread pattern it is, and head shape. it looks like it is tapered head bolt but I don't know what size