1988 80q 5 bolt conversion questions

[blarson at Zeiss.com]

I am interested in switching my 1988 80tq to 5 bolt fuchs wheels from a
5000tq.  For the rear I am planning on using hubs and rotors from a 5ktq
which I have, and in the front a4-1.8tq hubs and 5kq g60 front brake rotors
with g60 front brake calipers.  I know the hubs will press into the
bearings on all 4 corners, and all of the splines will be correct, but my
question has to do with brake offsets.  Are the rear 5kq rotors the correct
offset, or do I have to redrill a set of 80q rear rotors?  Also, are the
5kq front rotors the correct offset for the a4-1.8tq front hubs?  There is
another rotor with a different offset that could be redrilled, the 90q20v
g60 front rotor, but I am wondering if anyone has experience with this to
help minimize my downtime.

FYI, the car has 4000q style control arms front and rear, 2 piece front
struts, and 1 piece rear struts (early build 80q).  I am trying to
standardize wheel bolt patterns between several cars, and also upgrade to
larger g60 brakes after my turbo conversion.  Also, has anyone corrected
their speedometers going from 14" to 15" tires, does the speedo gear from a
1991 200tq accomplish this, or is an adjustment in the cluster possible)?

Also, when doing stud upgrades what wheel stud have people used these cars?
I am thinking Porsche 911 14mmx45mm studs look pretty good with steel lug
nuts and the seat is correct, and would allow spacers to be used if
necessary, but is there a preferred stud people have used in the past?

I will post the results to the archives when I am done.

Thanks for the help,
Brian