the hardest part is going to be the shifter linkage.
Good call, do you have all the 5 speed shifter pieces?
Do you have an engine hoist? I would drop the engine and lift the truck up over it.
Does the 5 speed have the driverside mount on it already? It is different then the 4 speed one.
Loosen off the axle nuts (30mm) before you jack the truck up. Do not roll the truck around without the outer axles installed or you will destroy your wheel bearings.
says who? how would that destroy anything? the axle is fastened to the hub, not the wheel bearings. the wheel bearings still have load on them anyway. how does the axle not being there have any affect on it? i just dont see how this can even be possible? cause ive rolled plenty of VWs around with no axles, and even for some longer distances, and the bearings faired just fine.
and superbro, if you try and take the engine out through the hood, you will know why we told you to go out through the bottom. just take our words on it here. or you can try doing it yourself. either way, the engine will be going back in through the bottom if you are smart.
and if you dont have the 5 speed specific mount, you are SOL. 4 speed ones are different enough its hard to modify them to even work.
and make sure the 5 speed going in has the same 90mm drive flanges. if it doesnt, you will need to swap flanges or build some axles. ive done both ways, and neither is hard to do. my rabbit has mk1 axles with mk2 100mm inner cv joints. my gti had the flanges swapped.
also, you need every thing basically besides the shift shaft from the shifter. there are more than one or 2 specific pieces. ive done a few 5 speed conversions, and never used the same combination of pieces twice. my rabbit was half 4 speed links and half 5 speed links, with a 5 speed shifter relay (the piece that bolts onto the splined shift shaft) and relay rod, going to a 4 speed relay ball, with a 4 speed rod from that. and the gear selector shaft was straight forward.