Is this a good road bike frameset to consider building for a 5'6" rider? Can this frame be used to build a decent road bike for someone 1.73m (5.6 feet)? It has 58cm ST, 58cm TT. 



7005 aluminum Easton Ultralite aero tubing. 1" aluminum threadless fork.

I'm coming from MBX and never even rode a road bike :)

What are the things i should look for? nothing too indepth, just the major mistakes i can make when starting with a frameset.

For one thing, is a 15yr old aluminium aero even a good choice these days?
Given the age of the frame, it's limitations in terms of component choice, and the size of the frame compared to what I would expect a rider of the height described by the OP to ride, I would say building this frame is a waste of money and time.

For a rider who is 5'6" tall, a typical frame size is 52cm. This frame is a 58 cm, 3 sizes large. Even if you have an unusual body type which pushes you to a larger than average frame, unless you are wildly out of proportion, you will not move up by 3 frame sizes. 

In addition, since the frame is alloy, and 15 years old, at least, there is the issue of metal fatigue to consider. While many people ride alloy bikes which are 10 or more years old, the useful, efficient life of an alloy frame is typically 5 years. Had you owned and ridden this bike for 10 years, so that you were familiar with its limitations, handling, and perhaps attached to the frame sentimentally, I might consider rebuilding it. Since that is not the case, I would not spend the money to build a frame with no useful life left.

And last, if you build this frame, it is likely that you will have difficulty sourcing properly sized parts, or will have to compromise with shims and adaptors to make the build work. I know that 1" stems are getting rare, and it's possible that the axle width on this frame is narrower than a typical modern road bike, although that is only guesswork.

All in all, I see many reasons not to build it, and none to go ahead. But at the end of the day, it's your bike, and your body. You will need to decide for yourself.