Realistically.....

[Haribo!]

ive just put my gti head on my driver bottom end, i haven't changed the cam belt, realistically am i facing problems if i don't change it, a few of my friends that have just started they're mechanics course told me its a must to change it but is that really necessary?

[Agreeable Slick]

it's usually a must do when messing around with the head.

One thing i am wondering is are you positive that EVERYTHING is at TDC?? if not it could cause untold problems. 

[Haribo!]

well thats just it, im very unsure as it goes, i made sure the roter arm was at #1 and that the 1st piston was at the top and that the little punch thing one the pulley thing was lines up with the mark on that bit of plastic bolted to the rocker cover saying "TDC", but ive read something about 6 degrees BTDC which i dont know what it is, my plan was to get it working then get it into a garage to get it fine tuned, but im beggining to wonder now....

[rubjonny]

Just get it done for piece of mind, do the tensioner at the same time.

All ytou need to do is remove the 2 bottom pulleys, the crank pulley is easy as the big bolt in the middle cabn be used to hold the pulley still while you remove the hex bolts.  The waterpump is more tricky but I'm sure you can figure something out

Everything you describe for TDC sounds fine, don't worry about the 6degrees BTDC yet, that can be fiddled with once you have the engine running.

[Haribo!]

sweet, gonna do it now, ill let know hiow it goes