You need to look on your existing gearbox for the specific variant code. It's stamped into the casing on a flat section at the back, near the dogbone IIRC.
All of the manuals in the MK5 are the O2Q model, but there are variances for R32, diesel and GTI. Pretty sure the same box is fitted the GTI, Pirelli and ED30 though. R32 has shorter gearing iirc, if that takes your fancy. I know it does me. The stock gearing is way too tall.
The Helix clutch is OK if you get the newer one with their own billet cover plate. Their older kit which uses the Sachs sporting cover plate is f'kin terrible. Don't ask how I know.
There's a lot of internet hoo ha about DMFs being a necessity to absorb damaging engine harmonics, but many people are fine with SMFs. I guess the long term effects aren't known yet, but I f'kin hate DMFs. They are an utter abomination.
My clutch (helix) and DMF are fooked and due for replacement. Think I'll be going down the TTRS cover plate and OEM MK5 disc route personally, with a new OEM DMF. Pattern ones are garbage and last 2-3 years tops. Again, don't ask how I know 
Thanks for the great info as usual Pudding. I'm currently weighing up my options with the car. Apart from gearbox and the need for an exhaust ( The quality of the milek SS exhaust are shocking considering the price) mechanically she is sound, body work however is in need of some TLC and paint.
The gearbox is laying on the garage floor as I type as well as the exhaust. Not sure if it is worth rebuilding the gearbox, new exhaust and paint to get her where I want it or break her for parts ( No MOT failed on a holed exhaust). Be the best part of £2K to mechanically sort her and another couple of grand to paint. Absolutely loved the car but have fallen massively out of love with her just now. Not sure if I wait and see if the love returns and bring her up to scratch, fix the mech issues and sell on ( probably loosing monies in the process) or break out for parts 
Will do so reserch into pricing of the clutch kit I do like the sound of that clutch. Looks like you can get a pre made kit with a SMF or DMF. I have no noise off the DM or clutch slip but if ive gone to the trouble of removing the box would be insanity not to replace clutch, flywheel and release bearing when I'm there.
I have the luxury of a garage and time so could just fix in dribs and drabs ( Now own a caddy Maxi for everyday running and transporting the motorbikes to tracks). Cant decided what to do just now.
Looking at finding a replacement to get overhauled hopefully with a diff then stuck in the car.
Get in touch with Mart from Gas N Gears on Facebook - https://www.facebook.com/gasngears/
He can rebuild your box supply and install Quaif's cheaper than Awesome or Darkside - very talented guy
Thank you very much for the info will give him a shout and see what the damage will be. Only issue is I live in central Scotland and have massively lost the love for her currently.
Yeah that is a dilemma that faces us all unfortunately. Persist with the old girl, or throw the towel in for something newer. The MK5 is now at that age where major components like steering racks, gearboxes, engines, turbos etc aren't far off writing the car off if the bodywork isn't minty fresh
I keep toying with the idea of converting to DSG but it's a faff and expensive. I don't have the luxury of a garage so it would have be dropped off somewhere for a few days, bumping up the final cost even more!
How bad is the bodywork? That can also write the car off if it needs a complete respray. I know mine does with the sheer amount of stone chips
Good wraps are now the same price as an average blow over, so which ever direction you take, it's big £££s.
I'd persevere with it personally. Bodywork can be done DIY to an OK standard if you're patient, just so long as it keeps the rust at bay, which is the main thing. MK6s and MK7s do nothing for me what so ever, so I'm trying to keep mine going for as long as possible also.
Agreed on Milltek. I really don't get the fascination with that brand. A lot of money for the averageness of the quality. I'd rather fork out for a new OEM system (if available) than go aftermarket tbh, but there are some good options in the USA though
