Front disk brake conversion

I believe that would depend on the backset measurement of the wheels.

If zero offset with the track not being changed - you should be ok.  The front has a lot more room to work with than the back wheel openings.  I added 1/2" spacers to push wheels further out in front (plus clear calipers and allow for a billet center cap over the front wheel bearing caps).  On a classic (non-flared) body, the rear can be a real issue with long/short axles changing rear stance.

Thanks for your replys. 

So a 5 wide rotor will make the front end wider? 

Would you venture too guess how much? 

I'm not sure if I understand what zero offset means, and how it affects front end geometry?

Is there a kit that most people use, my frame is custom tube chassis. 

Thanks 

The zero offset should mean it is identical to the OEM drums track --- so identical track to OEM. If it doesn't specify zero offset, at least on 4 lug dropped spindle conversion, you'd get 1/2" more track per side.  What could happen though is since the calipers stick out further that drums - depending on offset of rim and design of rim, they could hit the calipers (so grinding of the calipers to clear or use spaces to clear).  Using 16 rims I can't see that this would be an issue.

Are you using really old wide 5 16" OEM rims?  You don't see a lot of new wide 5's in 16". The new Vintage 190 aluminum wide fives are only 15".

Thanks Wolfgang, yes the ff/cnc kit is pretty early. 

Here's a picture of my wheels.