Need some advice on 454 Riser Replacement

Been a while since I posted on

Been a while since I posted on here so the boat is a 1988 29' Blackfin with twin 454 model 350 crusaders. The manifolds are the "log" style. I decided to replace my risers this off season. I started this project a few days ago and have run into a few snags. I have 9 out of 16 bolts out. I am having trouble with the lower bolts on all four risers that are closest to the valve covers. Is it possible to use a socket on these bolts. I have been using a 12-point wrench and seem to run out of room on these bolts. I have three others that are partially rounded. Any tricks or advice is welcomed. Thanx -Brian

"I have a cut down a 9/16 open

"I have a cut down a 9/16 open end/box wrench for this very job . Only the box end is left and I even had to grind down some of the box wall to fit this application. You can then use a much larger box wrench over the stub to make more leverage. But, I was using 6 point bolts back then, now using 12 point bolts, which I recall are only 3/8" head size.
Others will have good ideas on rounded heads, where even a normal socket or visegripa won't fit. Doesn't sound easy, for sure."

"Brian, I am only able to seco

"Brian, I am only able to second Dave's idea and have made the same mod to a 9/16 in order to fit it in place. IF I am not mistaken, and you have the same log/elbows combo I have, you may find a cut-off wheel helpful to grind theu the nut and stud. You are going to replace the elbows anyway and you can easily remove the stud once the elbow is off with just a visegrips. ONCE AGAIN, I ASSUME we have the same setup. ( ASSUME ...you know and A$$ out of U and ME) Good Luck"