Yep. Bolts on. Remove the stock three bolt flange and bolt my replacement unit on. I found a picture from the last job but its too large to post so Ill need to modify it sorry and I'm heading off racing sprintboats right now so next week. Unit is $400 bu itself or $350 if you send me your flange back. I do need to know if you are using the early 4 speed A341 / A342 or the later 5 speed A650. I often have them on trade me but I've been too busy for trade me sales lately.