Hi,
Questions: Can you add a three point seat belt? Yes, a 3 point kit runs about $230.00 parts, I would need to look at the 2 door falcon before telling you the labor.
How much does it run to convert front brakes to disc brakes? Parts add up to approx 850.00 for the basic disc brake kit and misc parts and the master cylinder etc... and labor would be approx 675.00.
Is the Geo Metro power brake method a good one? Unfortunately there is not enough room to do a power brake booster in a falcon.
It has an inline 6 with the two speed auto trans. Is there a better auto trans? A better automatic would be a C-4 three speed auto matic or upgrading to a 4 speed automatic that has an overdrive. Honestly I wouldn't spend the money to swap the transmission until it go out but that is up to you. A three speed swap is approx 400-500 and to a conversion to a 4 speed auto is closer to a 1000 in labor. Parts for the 4 speed automatic is what ads up quickly.
Bill, if there are any other questions you can also give us a call. We also do pre- purchase inspections for our customers so you know what your getting into.