Just finished the last of the four exams on 16th.
For the Law you will be fine if you just get all the 20 kilos of books out again and pour through them looking for helicopter references. An hour with an instructor pointing out the traps will be invaluable.
Perf you are going to need some help. I did two half days of groundschool (separated by a couple of months) to teach me the tricks of the exam. Wouldn't have passed it without. Depends on your area but give a school a ring and see what they charge. A case of Crownies might do it for an impoverished instructor (ie all of them...)
For CADH you really need to get a copy of Wagtendonk. The examiners already have. I tried to hack it with several very good helicopter aerodynamics books from around the world but the questions are looking for the Wagtendonk answer. It's very readable.
CSYH exam was half fixed wing anyway, hydraulics, instruments, turbochargers etc, but you'll need to read a book on helicopter systems to get your percentages up.
The other advantage of getting a school involved is that they may already have an account with AFT and marking credits so you can practice a few exams with them, usually for a very small fee. The exams are usefull, but the actual exams were a bit more tricky.
Best of luck with 'em.