And the answer to the wheel question is

Hi FABO. Trying to select a set of wheels and tires is a daunting task as most of us may know so this goes out to the select few.

Details are as follows: 68 Barracuda, 8-3/4 with 10x2-1/2 drums, Mopar 73+ disk brake conversion pending for front. Planned tire selection 205/60-15 and 225/60-15 on 15X7 w/4 in BS.

Per the details set forth in the article https://www.bigblockdart.com/threads/how-to-measure-for-proper-wheel-sizes.45889/ , have performed what was necessary to complete rear wheel layout. Before I continue, need to know what is the allowable back spacing is for the front with noted disk brake setup. Cragar offers a 15X6 with 3.3 in. BS, as well as 15X7 with 4 in. BS. Acceptable wheel width for 205/60 is 5.5-7.5". Can change my selection of wheels based on returned comments. Hope I've covered all the details. Thanks for your time. Jeff