Loosely mount the guide in the cylinder before putting the cylinder on. It will look like this, with the guide sticking out the top and hanging out the bottom .....
View attachment 350340
Now simply measure the gap between the sides of the guide and the tunnel walls at both the top and bottom, and "center" the guide if needed (see my pic in post #9). Do one end, snug the mounting bolt, do the other and snug it's mounting bolt, then re-check the 1st one to make sure it's still centered. When you get it centered correctly then you can tighten and torque the two mounting bolts to spec. Like I said, I don't think the factory even bothered doing this, but we can, and it's pretty simple.
I see many guys on here that drop the cylinders in place then stick the guide in. I tell them that's wrong, that they won't be able to accurately center the front guide now. Sure, they can center the top, but who knows where the bottom is at? Some pull the jugs back off and do it right. Others don't bother, lol, figuring they got it right or close enough. It would be interesting to see those guides at the next rebuild, lol.
I consider "centering" the front guide an important "must do" thing when doing a rebuild, but I haven't seen it mentioned or elaborated on in any manuals. Maybe they just consider it a "common sense" thing? Well, it is really, if you think about it, but I doubt many give it any thought, lol.
