How do I split the assembly so I can fit it to the chassis please

Google is your friend here Moggy, here is a detailed link , best to get the seats out for full access

Good Luck

https://www.google.co.uk/search?.q=classic+vw+beetle+pedal+assembly+diagram&biw=1366&bih=673&source=lnms&tbm=isch&sa=X&ei=MGMEVf-gNsPpaJL-gfAL&ved=0CAYQ_AUoAQ&dpr=1#imgdii=_&imgrc=enr_FXHhUY-kAM%253A%3BHE1hKwyeq3jbgM%3Bhttp%253A%252F%252Fimages.thesamba.com%252Fvw%252Fgallery%252Fpix%252F866160.jpg%3Bhttp%253A%252F%252Fwww.thesamba.com%252Fvw%252Fforum%252Fviewtopic.php%253Ft%253D488523%2526view%253Dnext%3B627%3B380

This might be better

http://chircoestore.com/tech_articles/?p=362

On my 1970 onwards pans they normally go in fully assembled the hard bit is getting the clutch cable hook into the tunnel hole and folding the pedal assy down to the pan, the already fitted accelerator shaft pushes through fully when it is down.

On my 1970 onwards pans they normally go in fully assembled the hard bit is getting the clutch cable hook into the tunnel hole and folding the pedal assy down to the pan, the already fitted accelerator shaft pushes through fully when it is down.

WHS^^^. Hold the clutch cable loop onto the hook with a thin cable tie (it'll just snap off when you start using the clutch). Don't be tempted to cut an access hole in the tunnel as this will seriously weaken the chassis structure.