Right well, I can't really give you much advice on this myself, but I have the same conversion planned for my GSi in the near future, but I can say I doubt you will get everything done in 5 days, its a big job changing an engine, (not to mention custom fitting parts that were not supposed to be in an astra!) and even with all the right tools etc, you will always encounter silly little problems, what gearbox you planning to use with this conversion anyway?
It took me and a mate 2 days to remove a C20LET and F28 from a calibra and remove my XE and fit the LET and F28. It was the Piping up and wiring, and all the fiddly bits that took the most time (2 1/2 days) then after that i took it for the Exhaust sorting.
You can do it 5 days easily. Once everythings in, it'll take a while for the little bits but within 5 days you should have everything up and running. The exhaust is the only part you have to rely on someone else if you can't do it yourself so make sure the arrangements are taken care of.
if you heard the engine running before you bought it you should do it in five days no problem at all,mine took longer but i had loads of running problems after the conversion which was my own fault for not doing the above