I have a number of ways I line the pipe laser up. A lot of it depends on where I'm working (how critical being exact is, depending on city or inspector) and/or if I'm having to tie into an existing manhole. I've got a job going on right now, where we're replacing an 8" clay tile line with 10" ductile. I'm replacing all the existing manholes in between, instead of re-habbing them, so hitting them dead center isn't that critical. But the one where we are ending was. I have a Topcon AG-30 Theodolite surveyor transit that I use most of the time to line up. It just takes me a couple of minutes to set it up, and it's dead on accurate. I've also stretched a stringline, and hung a plumbob off of it, or even just eyeballed down a straightedge such as a level. Something I always do, that I know a lot of guys don't, is shoot my grades either with the transit, or rotary laser, and check to see if the percentage is right. We ran the percentage the engineer gave us on this job to the next to last manhole, then had to change the percentage on the last run, because we were going to hit the manhole .8' BELOW the manhole. I told the surveyor that when we started, and he supposedly checked it, and said they were right... Well, turns out I was right, so we had to change it. Which didn't surprise me much, since their centerline stakes were off too. We would have hit the existing manhole 1' south of center if we had used their stake. Have I mentioned I don't get along too well with most engineers or surveyors??? They tend not to like you much after you prove them wrong...