66/7N motor Q's

hi i have a single carb motor i pulled from a 66/7 fastback. i have never played around with T3's so this is all new to me.

firstly. it seems to have a 6V 200mm flywheel. is this standard?

secondly. if possible i intent to ground test the motor but the exhaust on it is very rusty, will a set of beetle extractors and j pipes clear the fan/tin for testing?

lastly (for now at least) i have both halves of the dip stick setup, but the rubber bellows are no more. how far apart should i space the bottom of the body mounted section from the top of the engine mounted section to get an accurate dipstick reading when i refill the oil?

thanks.

henry.