Bicycle Mechanics - Bottom Bracket Compatibility

I have an 89 Centurion DLX in superb mechanical condition. Eventually I want to put all the parts I can onto a Surly Pacer frame/fork.

I want to use the stock bottom bracket that came with the bike, and the crankset is a 6year old 105.

Is there anyway to determine if this is all going to be compatible before I take everything apart?

Measure the widthe of the BB. 68mm is English, 70mm is Italian and 73 is mountain bike.

I'm may be misunderstanding something in the original post. I believe that both frames will have a 68mm english threaded road shell so that any bottom bracket that fits in one will fit in the other. But the Centurian's original bottom bracket would have most likely been a square taper where as a 6y.o. 105 crankset (5500 series) would need a splined Octolink bottom bracket.

C3hamby, we are confused. Is the stock bottom bracket and the 105 crankset is already mounted and working on the Centurion? If it is, you should be fine as long as the Surly is also 68mm BB shell. If it is not, as canam73 said the 105 may be Octalink2 BB.
Other things to think about are the stem may not fit since the Surly pacer's appear to sell threadless setups, so this means may need a headset and spacers (bearings for steering) and a new stem. Probably handlebar tape after you take the stem off, I would suggest new cables (inner and outer), chain possibly depending on length of new frame stays (chainline is an entirely different subject), and front derailleur depending on the new frames seat tube diameter. Are both frames designed for 700c wheels? Make sure the centurion isn't 27" or you may have brake problems. Im sure it will look awesome after, have fun!

To clarify, I have a Centurion frame that I want to pull the bottom bracket and the 105 crankset off of and move over to the Pacer frame. The bike is currently in operating condition. Unsure about squared and tapered but the 105 is currently properly attached to the bottom bracket.

I should have said that I am going to move over all that I can, as I know that some things cannot be moved over.

As to the fork, I am indeed going to use a more modern headset and new stem. As for the brakes, I am going to upgrade to a more modern STI set up. Definitely need new handlebar tape as I will have none once I remove the old cables.

The wheels on the Centurion are definitely 700, but because of the age of the wheels(I break those 20 year old spokes everytime I ride it)and the desire for better wheels and hubs those won't carry over.

Ok, you should be good on the crank/bb then. Do you have tools for this stuff?

I have some of the tools. We have a thing in Austin which is called the yellow bike project...on Fridays they open up the work stations for free and you can do anything you want, they provide everything, they even have a lot of parts, but probably nothing I would want to use on this build.

They also offer assistance but they make you do the work. Once a guy showed me how to thread the pedal and got it all the way on, and then he took it off and made me put it back on. That is where I replaced the old bio pace with the 105.

I just didn't want to get down there with everything and find out I needed a new bottom bracket.