back spacing me out

First off I would like to say, I am new to the forum and mopar muscle.

I recently picked up a 69 RR from a friend and am learning the mopar way. Things are different compared to my 69 mustang fast back 428CJ.

Anyway I have been reading for hours on wheels. Specifically the backspacing needed to clear disc brake conversions.

When I purchased the RR the previous owner included a disc brake conversion kit (MBM) and complete front end rebuild kit (just suspension).

My question is can anyone tell me what wheels and tires I need to purchase to fit with the disc conversion? The manual just says “must use 15" wheels”.

I did read a long article in mopar muscle mag that shows how to measure for backspacing, but they lost me when they started explaining how to measure the front. I guess what I am begging for is someone who has done the math to spoon feed me the dimensions.

This will be the only time I beg for a handout:binkybaby:. From now on I will be sure to contribute to this forum. I am running out of hair to pull on this one.:icon_hang:

Thanks in advance

15X7 with 4" backspacing is plenty to clear the brakes.
15X6 with 3.75" backspacing is acceptable.
That's what the factory used in later years with factory disc brakes,..
0 offset,+6 offset is good.-12 may not clear--test fit first before mounting the tire.
Anything with a big positive offset is best left for the FWD ricers,IMHO.
Here is a site i use-play with it and it will give you a better visual understanding of backspacing and offset.
Hope this helps
http://www.rimsntires.com/specs.jsp?item=Wheel-Tire