converting GT2560 revA to 24V

[ice0]

Hi!
Im thinking to converting my printer from a 12v system to a 24v one.
I know the board can support 24V, but i want to be 100% sure before i fry something...
My question are:

1) i just need to buy a 24v PSU and connect it like the original one?

2) and what about the fan? now im using 12v fan for the hotend and the part cooling fan, can i keep those or i need to replace with the 24v variant?
in the manual i found this:
2.4 Fan connection
As default, no matter the power supply is 12V or 24V; you need to connect the 12V fan as ther
e is a separate chip that can provide power supply for the fan. If you choose the 24V fan and 24V po
wer supply, you need to connect the JP2 with jumper cap. As shown in the picture.
Note: this function is only available for versions after REV A.

because i have the REV.A board, that means i can use 12v fan with 24v psu without problem? i just need to remove the jumper on JP2?

3) the 5V pin near the mega2560 chip will still valid even with the 24v power supply? any other 5v power source?

thanks in advance!