Trading for a 1985 635CSI

So, I'm trading my 1999 740iL, which I have been very happy with, for a 1985 635CSI with 130,000 miles. I am trying to get the guy to put between 3k-5k on top of the trade so I can reinvest my money back into my new 6 series. Not including blacking the car out, these are the mods that I plan to do;
1.) Add a Sterling Coated Header for Manual Transmissions Only : $749.95 USD
2.) Add a Tri-Flo Performance Exhaust System - twin 3" round tips : $939.95 USD
3.)Add a Schrick High Performace Camshaft -284 Degrees : $699.95 USD
4.) Add a, if applicable, Bavarian Autosport Performance Chip ECU w/ 24 pin chip : $249.95

Total: $2639.80
My question is not only does this sound like a safe investment, purchasing a car with 130,000 miles and a broken odometer, but would these modifications really add a large amount of horsepower/torque?
Thank you,
Mike