You could, but would be expensive and might violate emmision laws. You state client, if the Escort is in exchange for services you performed, you might suggest your client sell the car and pay you cash, or take the car yourself and sell it. Or, as above, have someone teach you how to drive a manual transmission, easy to do.
Not impossible, but not practical either, unless you are doing the job yourself and just want to see if it can be done. Otherwise too expensive. If you switch to a manual transmission, expect hard to debug computer configuration problems. With high fuel prices a small car with a manual should be worth something right? Why not put up an ad online to see if someone wants to trade it for an automatic?
It will be nearly impossible to convert this 26 year old car to an automatic transmission correctly. And the car is worth almost nothing so it is NOT worth the labor to install an automatic. This is a lot more difficult than it sounds. I looked into this when our Camry was destroyed in an accident. It had a very rare configuration, which was special-ordered new by my father: automatic transmission with hand-crank windows, non-powered seats, no sunroof, no security system, etc.
What a shame, because I really liked that car. Why do you say that? Basic disposable transportation when it was new. A free car nowadays is manna from heaven. If a used transmission was installed then there is the lingering question of whether that used unit you just installed is any good. I looked at Craigslist prices for manuals 4 cylinder to verses automatic. The prices for manuals seem to be a bit higher, but there seem to be be more exotics and trucks in the manuals category.
I had an '89 Escort with a 5-speed. It was an earlier design but the ones with automatics were rated at around 30MPG. My 5-speed got 41MPG on a 50 mile commute.
