Checking the ignition timing on a QV

I think this would be a good topic to bring up. I have not done this yet on my car but would like to discuss it.
On the QVs the timing is factory set and can't be changed with the stock dist.
My manuals shows 3 ATDC with vacuum line connected to the plenum and 6 BTDC with the vacuum disconnected.
Anyway, do you guys check it with the line disconnected? Also cylinder #1 is the plug wire closest to the timing belts on the 1-4 bank (the bank is the one facing the rear tail lights)
Any additional info can be added. I just thought I would put some of this info in here.

Hi Rich,

you are correct, cyl. #1 is the cylinder nearest the belts on the back bank, on the front bank, cyl #1 (#5) is the cyl. nearest the distrib cap.

The timing is checked thru the inspection port on the top of the bell housing, that is covered with the small aluminum plate and held in place with two 5mm nuts. Once the ccess hole cover is removed the flywheel is visible thru the hole. Along the flat edge of the flywheel the timing marks and numbers are found stamped in the surface. The corresponding marks should align with the pointer at the appropriate rpms. Timing is checked with the vacum line connected as the digiplex units also use the vacum to determine timing advance.

Regards, JRV