Don't do it unless you have a decent mechanical knowledge and a shedload of spare cash otherwise it'll turn out half arsed and piss you off.
I restored my 1984 Mk2 Golf over a period of 12 months from right back to bare shell, extensive welding as it needed new floors, chassis points, inner sills, outer sills and patches here and there. Everything underneath was replaced for new original VW items down to the last nut n' bolt/washer apart from upgrade items such as Eichbach anti roll bars & springs, Bilstein B12 shocks,powerflex bushes, uprated brake calipers/master cylinder/pads/discs. Also replaced a lot of dodgy and tired wiring, fitted an ABT tuned 1860cc 16v engine with 192bhp that redlines at 8000rpm, rebuilt gearbox with a quaife diff, handmade stainless manifold and stainless jetex exhaust, modified fuel injection system to cope with the extra demand (which is a pain to keep on tune if i'm honest) all set up on 4 wheel alignment for camber etc, full restored leather interior and nae back seat coz my bike lives in the rear :D.
All in i have receipts totalling near enough £5000 and i've still to budget for a full respray as i can't afford that at this point - even at mates rates that's gonna be another £1000+, i did all the work myself as i trained as a vehicle mechanic 20 years ago and i'm quite decent with a welder.
It won't be cheap, to be honest you'd be better heading to the south of spain and buying a decent Mk2 Golf, driving it back to this country and carrying out a resto job on one that hasn't been attacked by rust as there are so many dogs out there for sale cheap.
My golf still needs new exterior plastics and trim as they do go grey unless i get the trim revival out and i've only done that a couple of times in the past year since it's been back on the road, original trim is pretty rare and bloody expensive so i may not bother, it also needs a front valence but i can't find an original one anywhere so i may end up making a splitter - mine is by no means in A1 bodywork condition but i know everything regarding running gear and brakes/steering/suspension/ball joints is A1 condition so i have confidence in the car when i do choose to boot it, shows a clean pair of heels to the lardy Mk6 gti.
Every floor needed extensive and awkward welding to tie all the weld points together
I managed it though
I only meant to change the rear pads n' discs for the mot but soon realised as i poked about it that it was fubar'd in the current condition and needed a lot more work so off it went up to the workshop on a flatbed, and 12 months later it came out spitting and barking on the overrun, was it worth the hundreds of hours and thousands of £ i spent on it?, my head/bank account says no way can it be justified, my heart says ****-yeah! - especially on a tight n' twisty road