Nice information on this site for many years and since Ive been asked about it this could be a good option for high rpm builds already using arp bolts.
I might be doing this to my modded L20b crank.
http://www.guy-croft.com/viewtopic.php?f=3&t=900

thats meticulous...

If you were going to go to that length, you'd oversize your dowel holes, and fit them with hardened guides so that they were always in the same place. (I have hardened guides on my S13 adapter drilling jig)
IMO, you'd need to be doing a few of them to warrant making up a jig. I only run two 5mm silversteel dowels on my car. (Loctited in) They're both in on the same PCD, and 180 degrees opposite on another. (For the sake of balancing)
I figure that the cap screws Can hold it on fine. The dowels just serve to take out that tiny bit of movement that allows them to shake loose.
The factory set up is so lacklusture, that my flywheel (Which was balanced along with the pressure plate, doweled to my crank) when fitted to another crank (To have a new pressure plate balanced) ran out of balance on a very sensitive Sunnen balancing machine. (The same one it was balanced on to begin with) And that was just bolted to another crank!

The fiat crank in the pic is also Non FCW like the A series.
The FCW L series crank dont suffer these issues as much but
Im getting it done for that extra insurance.
I have never come across an A12 with lipped spring plates
that provide that extra security as found on A10 cranks and
its something I like to use also on other A series engines.