I have done this M2300K brake conversion on my '88 LX Coupe, actually back in '96 or so. Has been an excellent set up. A lot of work to put on but fun and very rewarding.
17x6?? Assuming that 6" is a typo..
As to wheels, any OE Bullits or OE wheels sized 17x8 w/ 30mm offset (5.75" backspacing will work out. 1998 Cobra OE wheels at 17x8 look very good too. At the time Ford Motorsport recommended the Cobra R wheel made in these two offsets: 17x9 front, 24 mm offset, 5.95 b/s; and 17x9 rear, 36 mm offset, 6.42" b/s. I ran this set up back in '98 on a 255/45 17 tire and it worked well.
Over the years I ended up going w/ a staggered wheel set up and have found this to suit perfectly:
- 18x8 30 mm o/s (5.75" b/s), 245/40 18 tire (seemed there was always a turning compromise running much more than 8" wide)
- and 18x9 45 mm o/s (6.75" b/s), 275/35 18 tire (the key is that 45 mm offset, tucking the rear wheel in more, this to overcome the longer rear axles that are part of the M2300K set up)
Be sure to measure your car carefully as each set up is different depending on springs, exhaust, and other modifications.
Here is my car:
No rubbing and full turns. Car is on Eibach springs.