What if any modifications will I have to do to put 17" wheels on my '77Z. Motor sport hhas some for four lug and i'm window shopping for now.

 

It depends on the wheel offset and bolt pattern. To install RacingHart C2's on my 240Z required adapters made by MML (Ross' business). They were 28mm thick. The C2 bolt pattern was the same as the Datsun (in this case). They cost me about $225.00 as I recall. Nothing rubs and the look is awesome.

 

I just bought my 73' 240Z and it has the 17X7 Enkei Wheels on her... Here is a link to see the fit. The spacers were installed... can't say what they are as I have no data as yet... I like the look, but I am thinking of going to another look I have always liked... Panasports... I may have this set up for sale sometime soon... http://www.theguitarweb.com/bluez.htm

 

Try getting steel wheels made with the proper offset.
Cheeper than mags and wheel studs wont be damaged.
Easier to change wheels and balabce.