I have a 1966 Mustang (Coupe) with Stock Drum Brakes and I am looking into Purchasing a Front Disc Brake Conversion Kit and am looking for Recommendations on Disc Brake Kits.
if u want cheap but good bang for your buck do a 79 granada swap. I have done 2 with good results. pick up spindles at junk yard and new rotors and calipers at auto zone. also have to change outer tie rod ends. if u have power steering u will need special made tie rod end for drivers side. u can get that part from mustangs plus. you can do it for a fraction of the cost of many aftermarket kits, with quality Ford parts.
You could also get brand-new spindles from discbrakeswap.com ("deigns" here on StangNet) or for that matter 70-73 spindles from a junkyard; and go to ultrastang or MustangSteve (or, maybe by then, "deigns" again) for brackets and go to SN95 rotors/cailpers.
Two provisos for this plan: 1.) Same story on rhe tie-rod ends as bartman mentioned. 2.) You will need new wheels - and they will need to be larger in daimeter. The original 14" rims won't fit over the bigger rotors.
Degins has a granada conversion kit that has spindles with the correct geometry for the 65-66 cars, none of the other granada conversions have this. you can also use a stock 65-66 disc system as well but they'll be more expensive than the www.discbrakeswap.com kit.
you really need the spindles with the correct geometry if you plan on using big, wide sticky tires and performance suspension pieces. if you plan on keeping stock sized wheels and tires and stock style suspension you can get away with a stock granada conversion or 67-up disc brakes but personally i'd use the stuff with the right geometry for the car, either Degins kit, the stock 65-66 disc brakes or one of the many kits that use the stock drum spindles.
i don't think Degins has the kit with the correct geometry spindles listed on his site right now but just send him an email if you plan on ordering one of his kits and he'll set you up with the right one.